What are the 4 types of cognitive bias?

According to Buster Benson's cognitive bias codex, every time a user interacts with a product, they :

  1. 🙈 Filter information
  2. 👀 Search for meaning
  3. ⏰ Act within a given timeframe
  4. 💾 Store elements of the interaction in their memory

So, in order to offer your users a memorable experience, you need to understand the biases that affect these 4 stages of the decision cycle.

Here's a list of 109 cognitive biases (with examples and tips for each) that strongly influence your users' thinking and behavior.‍

PS: No time to explore the whole list? Then all you have to do is download the cheat sheet at the bottom of the page.

PS 2: The idea and structure of the page are inspired by Growth Design and Buster Benson's codex.

What is a cognitive bais?

Although people like to believe that they are rational and logical, the fact is that they are continually under the influence of cognitive biases.

The human brain is powerful, but subject to limitations. Cognitive biases are often the result of your brain's attempt to simplify information processing.

Prejudices generally function as practical rules that help you make sense of the world and make decisions relatively quickly.

Why is it important to know about the different types of cognitive bias?

As a consumer or marketer, this will help you better understand how your brain works. The more you know about cognitive biases, the better you'll be able to understand how a product/customer works.

For a consumer: it's easier to see if a company is using these principles in an unethical way.

For a marketer: it's possible to leverage these cognitive biases for your website to increase your conversion rates by enabling :

  • Make your site navigation more intuitive and fluid for your visitors.
  • Reduce the bounce rate (the number of visitors who leave your site before finalizing their purchases or simply before finding the information they were looking for).

It's what we call design psychology. And it's what helps you make the right design decisions for your users.

🙈 Filter information.

Users filter out much of the information they receive,
even if it is important.


Visual hierarchy.

It's a logical structure of elements, arranged in order of importance.


Definition Visual hierarchy.

Visual hierarchy is the principle of structuring and organizing elements in order of importance.

The role of UI designers is to structure user interfaces, to make content easier and more fluid to understand.

By arranging elements logically and strategically, visual hierarchy influences users' perception and guides them towards the targeted action.

Examples Visual hierarchy.


In art and web design, any area of a composition devoid of visual elements is called white space.

This white space allows the visual elements of a web page to breathe, thus contributing to visual hierarchy.

In design, the composition of an illustration or any other element on a page allows you to play with visual hierarchy.


Bringing elements together creates groups. This is known as the law of proximity.

Without these groups, it would be more difficult to understand and differentiate elements such as navigation, content or advertising.

This would make it more difficult to know where to focus attention and which elements can be ignored or not.

On the Spotify app, you can see 3 different groups.

Increasing the space between groups makes each set distinct and individual. This hierarchy enables users to identify more quickly the element with which they want to interact.


Tips Visual hierarchy.

  • People read from top to bottom and left to right. Organize the content of your pages in an "F" shape (blog posts) or in a "Z" shape (site pages) to make reading easier and more fluid.
  • Size matters. People read what's biggest first. Make sure you make the most important elements bigger.
  • Let important elements breathe. Isolated elements attract attention. Large spaces around a button make it easier for readers to see.

Hick's Law.

The time needed to make a decision increases with the number and complexity of choices.


Definition Hick's Law.

Hick's Law (or Hick-Hyman's Law) states that the more choices a user is presented with, the more time and effort it will take to make a decision. Named and theorized by psychologists William Edmund Hick and Ray Hyman.

Examples Hick's Law.


We all know the pain of scrolling through the endless list of Netflix content, only to find that an hour has passed.

It's not easy to make choices when you know the breadth of what's on offer in the Netflix catalog.

To help users reach quicker conclusions, Netflix recently created a new section called "Top 10 in your country", which lists content according to popularity and percentage of viewing in your region.

Exemple de la Loi de Hick pour offrir à ses utilisateur une expérience mémorable

In this way, Netflix makes it easier to decide on the abundance of choices offered by its platform, while at the same time highlighting content approved by a large number of its users (social proof)


Tips Hick's Law.

  • Try reducing the number of options or finding ways to hide certain elements. Do they all need to be displayed at once (Progressive Disclosure)?
  • If you can't reduce the number of options, try to present them in an easy-to-navigate order, and make sure the elements are familiar to the user.

Confirmation bias.

People are more likely to accept or pay attention to information if it seems to confirm what they think.


Definition Confirmation bias.

The fact that people are more likely to accept or perceive information if it seems to confirm what they already believe or assume. This is especially true when the situation is important or personal.

Examples Confirmation bias.


An example of confirmation bias that is both fascinating and terrifying is Google. Yes, Google...

The results of numerous studies show that search engines can reinforce confirmation bias by generating results that consist solely of evidence confirming what we assumed before our search.

"We're all vulnerable to bias. Internet search engines are the epitome of confirmation bias, and you want to use them as evidence to prove you're right?" - Neil deGrasse Tyson

Neil deGrasse Tyson, born October 5, 1958, is an American astrophysicist, planetary scientist, author and science communicator. Educated at Harvard University, Tyson is one of the world's most popular American scientists.


Tips Confirmation bias.

  • Remember to rephrase. Think carefully about what constitutes an authoritative source before doing your research.
  • Cross-check your sources, don't stop at the first piece of information you find.
  • Avoid asking questions that already imply a certain answer.

Survivorship bias.

Only noticing successes can make you blind to the failures.


Definition Survivorship bias.

Survivorship Bias occurs when we focus on successful outcomes, overlooking the failures.

Picture this: You're scrolling through social media and see a post about a college dropout who became a billionaire.

You think, "Wow, maybe formal education isn't that important after all." But hold on a second.

What about the countless others who dropped out and didn't strike it rich? They're not in the headlines, but they're part of the story.

That's the Survivorship Bias - the mental shortcut where we focus only on successful outcomes.

In web design, it can mean emphasizing elements that successful users interact with, neglecting potential roadblocks for others.

Examples Survivorship bias.


Airlines observe Survivorship Bias when they only pay attention to successful planes, neglecting those that suffer accidents.

During WWII, the U.S military wanted to add armor to their aircraft.

They studied planes that returned from missions and noted where they took the most bullets. They planned to add armor to these areas.

However, a statistician named Abraham Wald pointed out their Survivorship Bias.

They were only studying planes which had survived their missions despite their damage. The damage on these planes wasn't fatal.

The planes that didn't return, that they weren't studying, held the key to fatal areas to up-armor.

By overcoming Survivorship Bias, they effectively armored their planes, saving countless lives and altering the course of war.

Survivorship bias example with planes

Imagine if Netflix were to base its recommendation algorithms solely on the viewing habits of its most engaged users.

In such a scenario, the platform would only be considering the 'successful survivors,' or the most active viewers, potentially leading to skewed recommendations.

This would mean ignoring less active users and their diverse viewing preferences — these are the unseen "planes" that didn't make it back in our analogy.

In this case, a smarter approach would be to consider the viewing habits of a broader audience, including less active users, or a personalized recommendation.

This would aim to deliver more diverse and accessible content suggestions, providing a more balanced user experience.

Netflix' recommendation example for the survivorship bias

Imagine if Amazon's product review algorithm initially favored items with lots of positive reviews.

In this case, the platform would be promoting the 'successful survivors,' or top-rated items, while sidelining lesser-known or newer products with fewer reviews.

This would mean overlooking products that, despite having fewer reviews, still had high average ratings and satisfied customers — akin to the "planes that didn't return" in the Survivorship Bias analogy.

A smart move could be to introduce something like a "Verified Purchase" tag for reviews (which is what Amazon does by the way).

This would give more weight to genuine, high-quality feedback over sheer volume, aiming to offer a more balanced showcase of products that caters to diverse consumer needs and preferences.

Amazon's "verified purchase" as an example of the survivorship bias

Tips Survivorship bias.

  1. Listen to the 'Quiet Ones'. Don’t solely rely on successful examples when designing your website. Also consider customers who left the site or abandoned carts and try to understand why.
  2. Learn from bad experiences. Conduct regular user testing and study unsuccessful interactions. Use this data to tweak your design and improve user experience.
  3. Don't Ditch the 'Underdogs'. Regularly re-evaluate your choices while designing. Ensure not to overlook designs or features that didn't survive in the past but could prove beneficial now.


Fitts's law.

It can be used to estimate the time needed for a user to reach a given area.


Definition Fitts's law.

Fitts' law is a predictive model of human movement used mainly in the fields of human-computer interaction and UX.

This bias is used to predict the time required to move quickly to a target area.

Fitts' law is used to model the act of pointing, either by physically touching an object with the hand or finger, or virtually, by pointing at an object on a computer screen using a mouse.

Examples Fitts's law.


The image below illustrates the areas where it's natural for the user to interact with the screen and those where it's much more difficult. Try it out, you'll see.


On the mobile version of a website, it's important to position your CTA at the bottom of the page, and to ensure that it takes up the full width of the page so that it's easily accessible by the user.


Tips Fitts's law.

  • Clickable elements must be large enough for users to select them accurately.
  • Clickable elements must be placed in areas of the interface where they can be easily reached.

Cognitive Load.

The total amount of mental effort required to accomplish a given task.


Definition Cognitive Load.

Cognitive load refers to the mental effort required to use a website.

The lower the cognitive load, the easier the site is to navigate, understand, and interact with.

For superior user experience and higher conversion rates, optimize your website to lower cognitive load — eliminate unnecessary actions, convey information clearly, and simplify decision-making processes.

Why is it important? Our brains have a limited capacity for processing information.

By reducing unnecessary elements and simplifying tasks, you make it easier for users to focus, understand, and take action.

Examples Cognitive Load.


In everyday life, the notifications we receive on our phones are a major distraction that can cause a high cognitive load, making it almost impossible to process work-related information.

Just like computers, the human brain has a limited processing capacity, when too many stimuli demand attention at the same time, it saturates.‍

The same goes for websites, if your website overloads their brain with information, the only way for them to get rid of it is to leave your site.‍

People aren't going to use a website, let alone buy a product from an e-commerce site that exhausts and confuses them.

Every website requires a certain cognitive load, but the more you minimize it, the better the user experience will be.


Google's search homepage is a masterclass in reducing cognitive load.

A simple search bar in the center, with minimal distractions.

It's clear, concise, and lets users get straight to searching.

Google homepage as an example for cognitive load bias

Organizing a holiday and booking a house isn't a simple task.

There are dates to consider, amenities to look for, and budgets to stick to.

Yet, Airbnb manages to make this process feel effortless.

They guide users step-by-step, from selecting dates to making the final payment.

Each stage is presented clearly, minimizing the cognitive effort and making what could be a complex task feel straightforward and manageable.

First, you specify the destination, then check-in and check-out dates, and finally the number of guests.

Airbnb's booking process as an example of reduced cognitive load

Next, as you browse, the integrated map feature simplifies your search, allowing you to pinpoint your dream house in your desired location seamlessly.

Note Airbnb keeps your selected dates, location, and number of guests visible, offering the flexibility to adjust them on the fly without needing to return to the homepage each time.

Airbnb's booking process as an example of reduced cognitive load

Lastly, the checkout process is streamlined with your trip details prominently displayed, a clear breakdown of costs on the side, and straightforward payment options.

Airbnb's booking process as an example of reduced cognitive load

Tips Cognitive Load.

  1. Leverage common web practices. Build on existing mental models. People already have mental representations of how websites work, based on their past experiences of visiting other sites. Reuse them.
  2. Prioritize simplicity. Beware of over-stimulation and strip down your design to essentials only. A screen cluttered with information is nothing but chaos for the user.
  3. Reduce user actions. More actions = more effort for the user. Streamline processes to decrease user effort but don't compromise on clarity and comprehensibility. Aim for ease of use, not just simplicity.


Anchoring Bias.

Users rely heavily on the first information they see before making a decision.


Definition Anchoring Bias.

Anchoring bias is the cognitive bias that leads us to rely heavily on the first piece of information we are given about a subject.

When we make predictions or estimates about something, we interpret new information from our anchoring reference point, rather than seeing it objectively.

This can distort our judgment and prevent us from updating our plans or predictions as much as we should.

Examples Anchoring Bias.


A common SaaS anchoring technique is to make the most expensive subscription package (the anchor) more visible than the others (so that it is seen in first position), so that the other packages appear less expensive in comparison.


Another example from everyday life: supermarkets display their most expensive items at eye level with visible price tags, so that the item you end up looking for seems cheaper.


Tips Anchoring Bias.

  • Why are prices ending in 99 so popular? The explanation lies in the fact that customers cling to the number before the decimal point as an anchor.
  • By offering promotions, stores can encourage their customers to compare the sale price with the original price (the anchor point) to give the impression that they're getting a good deal.
  • By displaying your top-of-the-range services first, you encourage your customers to accept the prices of your other (cheaper) services.


Users' attention is drawn to elements that stand out.


Definition Contrast.

The Contrast Effect is a cognitive bias that distorts our perception of one thing when we compare it to another, accentuating the differences between the two.

It's a principle where distinct elements — be it color, shape, or size — stand out against each other.

This difference can guide users to key content, making your site intuitive and navigable, thereby increasing satisfaction, retention, and conversions.

Why does it work? Our brains are wired to notice differences.

When something stands out, it immediately captures our attention, making the Contrast Effect a powerful tool for directing user focus and actions on a website.

Examples Contrast.


Low-contrast text may look better, but it's also unreadable, difficult to read and inaccessible. Instead, consider solutions that are easier for your users to read.


A few years ago, Joshua Porter conducted a famous study entitled "The Button Color A/B Test".

He compared the conversion of two variants of the same landing page.

The only difference between versions A and B was the color of the call-to-action button.

Version A had a green call-to-action button, while version B had a red button.

Although Joshua predicted that the green button would perform better, the red button outperformed it, resulting in 21% more clicks.

Does this mean that red is the best-converting color?

No. It's likely that the red button attracted more attention because it was the only object to stand out on the page.


Nike's online store uses contrast effectively to drive conversion.

Their minimalist white background is starkly contrasted by their richly colored product photos.

This visual contrast grabs attention and guides user’s eyes directly to their products.

Their "Add to Bag" button is black, standing out from the white background.

Example of a contrasted website with Nike

Tips Contrast.

  1. Think Big, Think Bold. So the rule is simple: if you want users to interact with something, make it stand out! Amp up the size and weight of your key text to make it instantly noticeable.
  2. Clear Contrast, Clear Content. If you place text on an image, make sure it's legible by providing adequate contrast. Subtle adjustments can increase contrast without affecting the overall aesthetics of the site.
  3. Play with Space. Isolate important elements on big fields of white or dark space. Detaching them from other elements skyrockets their prominence and command attention promptly.


Aesthetic-Usability Effect.

Users see an aesthetic design as a product that is easier to use.


Definition Aesthetic-Usability Effect.

Users are more tolerant of minor user experience (UX) problems when they find an interface visually appealing.

The effect of aesthetics on usability can mask certain user interface (UI) issues and prevent problems from being discovered during usability testing.

In addition to generating positive feelings about a product, attractive aesthetics also evoke feelings of sympathy, loyalty and tolerance, all of which are important factors in the ease of use and long-term success of a product and a company.

Examples Aesthetic-Usability Effect.


Apple's success is an excellent example of the competitive advantage of attention to aesthetics.

They invest in the visual design of their physical products, as well as in their software, which helps mask UX issues.


Tips Aesthetic-Usability Effect.

  • Aesthetically pleasing design creates a positive response in people's brains and leads them to believe that the design works better.
  • People are more tolerant of minor UX issues and more likely to engage your services if the design of your product or service is aesthetically pleasing.
  • A visually appealing design can mask UX problems and prevent their discovery during usability testing.

Progressive disclosure.

Users feel less lost if they are exposed to complex functions later on.


Definition Progressive disclosure.

Progressive disclosure is a design strategy where information and options are revealed as users engage and delve deeper.

In other words, it postpones advanced or rarely-used functions until later in the user experience.

The aim is to reduce the risk of users feeling overwhelmed by what they discover. By progressively revealing information, designers reveal only the essentials, enabling users to manage the complexity of a website or application.

Examples Progressive disclosure.


Let's take Google again (an example we're all familiar with - familiarity bias), with a search for the keyword "best isekai". An article (written by me) appears in position 0.

This extract provides the user with just enough information to determine whether they want to go a step further and find out more, or whether the information provided already meets their needs.
Progressive disclosure is therefore one of the best ways of satisfying two contradictory requirements:

  • Users want an answer to all their needs.
  • Users want simplicity.

Amazon exemplifies Progressive Disclosure in its shopping experience.

Initial product listings provide just enough information, like the name, image, price, and star ratings to help you make an initial assessment.

When you click on a product, you then see a wealth of detail – more product specifics, customer reviews, Q&As, and comparatives.

This "on-demand" information keeps the website uncluttered, giving users control over their experience.


Airbnb's website and app utilize the Progressive Disclosure design principle effectively to streamline the booking process.

When users search for accommodations in a specific location, they are initially presented with a list of properties, each displaying a main photo, price, type of accommodation, and overall rating.

As users show interest in a particular listing by clicking on it, they are then provided with a more detailed view.

This includes a gallery of photos, a comprehensive description, amenities, house rules, and reviews from other guests.

For users who want even more information, there are sections for the host's profile, neighborhood details, and a Q&A section.

By revealing information in stages, Airbnb ensures that users aren't overwhelmed and can easily navigate the platform, making the booking process smooth and user-friendly.

Tips Progressive disclosure.

  1. Don't directly overload the user with all the information available about your product or service.
  2. Incorporate elements of suspense, progression and surprise by providing access to the right information at the right time.
  3. Don't assume you know what the user wants or appreciates most. Instead, discuss it directly with them.

Empathy gap.

People underestimate the influence of emotions on user behavior.


Definition Empathy gap.

The empathy gap describes our tendency to underestimate the influence of various mental states on our own behavior, and to make decisions that satisfy only our emotion, feeling or state of being at the time.

Examples Empathy gap.


A man plans to eat a healthy dinner, but is very hungry when he goes to the supermarket.

He buys junk food that he can eat immediately, instead of healthy food that needs to be prepared and cooked for dinner.


Tips Empathy gap.

  • The empathy gap in digital products is largely due to the increase in digital interactions and the scarcity of face-to-face contact, which has made it harder for brands to understand customers' feelings and reactions to their products. So watch them and talk to them.
  • Doing user testing helps bridge this “empathy gap” by enabling companies to understand their customers.

Von Restorff effect.

Users are more likely to remember elements that stand out.


Definition Von Restorff effect.

The Von Restorff effect, also known as the isolation effect, predicts that when several similar objects are present, the one that stands out from the others is the most likely to be remembered.

Examples Von Restorff effect.


On Hugo Décrypte's YouTube channel, the "ACTUS DU JOUR" tag is highlighted by a white tag. This is one of the only differentiating elements from other formats.

The tag makes it easier for Hugo Décrypte subscribers to identify this format, especially as Hugo has 3 channels and his videos are regularly pushed up the YouTube recommendations.


Another example, with Notion's pricing page. The use of orange for the button and the words "Invite your team for free" make the Team plan stand out from the other two.


Another, perhaps more familiar, example is the addition of a “new” badge to a product or service. Or simply the icon of an application and its unread notifications.

Tips Von Restorff effect.

  • Make important information or key actions stand out visually.
  • Be careful when emphasizing visual elements to avoid competition.
  • Pay particular attention to your important elements, including their contrast ratio, so that they are perfectly visible.

Selective attention.

People filter out relevant elements of their environment when they are concentrating, while ignoring irrelevant stimuli.


Definition Selective attention.

Examples Selective attention.


Tips Selective attention.


Banner Blindness.

Users ignore the elements to which they are repeatedly exposed.


Definition Banner Blindness.

Examples Banner Blindness.


Tips Banner Blindness.



When a user performs an action, the feedback indicates what has happened.


Definition Retroaction.

Examples Retroaction.


Tips Retroaction.


Decoy effect.

The addition of a third, less attractive option (the decoy) can influence our perception of the other two choices.


Definition Decoy effect.

Examples Decoy effect.


Tips Decoy effect.


Expectations Bias.

People tend to be influenced by their own expectations.


Definition Expectations Bias.

Examples Expectations Bias.


Tips Expectations Bias.


Centre-Stage Effect.

When faced with a set of products, we prefer the one in the middle.


Definition Centre-Stage Effect.

Examples Centre-Stage Effect.


Tips Centre-Stage Effect.


External trigger.

When the information on what to do next is in the message itself.


Definition External trigger.

Examples External trigger.


Tips External trigger.


Attentional Bias.

Users' thoughts filter out some elements while ignoring others.


Definition Attentional Bias.

Examples Attentional Bias.


Tips Attentional Bias.



Elements that are close and similar are perceived as one and the same.


Definition Juxtaposition.

Examples Juxtaposition.


Tips Juxtaposition.


Tesler's Law.

If you over-simplify a system, you transfer some of the complexity to the users.


Definition Tesler's Law.

Examples Tesler's Law.


Tips Tesler's Law.


Visual anchors.

The visual elements used to guide users' eyes afterwards.


Definition Visual anchors.

Examples Visual anchors.


Tips Visual anchors.

Priming effect.

Previous stimuli can influence users' final decisions.


Definition Priming effect.

Examples Priming effect.


Tips Priming effect.


Nudge theory.

Subtle clues can influence users' decisions, depending on how the choices are presented to them.


Definition Nudge theory.

Examples Nudge theory.


Tips Nudge theory.


Law of Proximity.

Elements that are close to each other tend to be associated with each other.


Definition Law of Proximity.

Examples Law of Proximity.


Tips Law of Proximity.


Spark Effect.

Users are more likely to act when little effort is required.


Definition Spark Effect.

Examples Spark Effect.


Tips Spark Effect.


Framing effect.

Users are influenced by the way things are presented when they make a decision.


Definition Framing effect.

Examples Framing effect.


Tips Framing effect.



Elements that communicate what they're intended to do or what they're used for.


Definition Signifiers.

Examples Signifiers.


Tips Signifiers.

👀 Search the meaning.

When users try to make sense of information, they create stories
and hypotheses to fill in the gaps.


Mental Model.

Users have preconceived opinions about how many things work.


Definition Mental Model.

How users think about a user interface has a strong impact on how they use it. Inappropriate mental models are commonplace, especially in the case of innovative designs.

It's all about how your users perceive your product, which influences how they use and appreciate it.

Examples Mental Model.


A useful example of adapting mental models is Apple.

For the release of the very first iPhone, they used a design process called skeuomorphism.

Skeuomorphism was popularized by Apple to encourage people to convert to the digital world. To do this, they created iconography that closely imitates real-world elements.

A typical example of Skeuomorphism is the trash can used to delete files.

However, as the world's population became progressively more technically literate, Skeuomorphism was no longer necessary.


Tips Mental Model.

  • Be aware that your users already have certain mental models in your industry, so it's important to be aware of this in order to offer them an intuitive user experience.

Familiarity bias.

People prefer what they know over what's new or different.


Definition Familiarity bias.

Users hate radical change. They much more prefer things they're accustomed to.

Why does this work? We humans are creatures of habit. We trust what we know.

When a website mirrors familiar elements, interfaces, or designs , it reduces our complexity, making navigation intuitive and boosting our confidence.

The aim is to reassure visitors they're on the 'right path', enticing them to stay longer and interact more.

Examples Familiarity bias.


Ever had that moment of calm when Google's clean homepage loads up?

Amidst the chaos of the digital world, there it is, unchanged: a logo, a search bar, and those two trusty buttons.

It's like that favorite coffee mug you reach for every morning. Simple, familiar, just right.

Even as Google introduces new features like featured snippets, "People also ask," and local business listings, the core structure of search result pages has remained consistent over decades.

An example of the familiarity with Google's homepage


McDonald's maintains consistent branding, store design, and even menu layouts across the globe.

Whether you're in Tokyo, Paris, or New York, the sight of those iconic golden arches signals a familiar experience.

It's like seeing an old friend in a crowd of strangers.

This familiarity ensures that customers, even in a foreign country, feel at home when they walk into a McDonald's.

Example of the familiarity bias with Mcdonald's restaurants all over the world.

The groggy stretch as the alarm buzzes, the familiar aroma of coffee brewing or burned bread - does it sound familiar to you?

That's the sensation when you power on an iMac.

The Apple chime and the iconic start up sound - legend has it this sound is a remastered snippet from The Beatles' "A Day in the Life."

Anyway, it's not just a computer booting up, it's a familiar, choreographed welcome so that every time you power on your iMac, you know what to expect.

Like slipping into your favorite pair of shoes, turning on an iMac feels intuitive, familiar, and oh-so-personal.

The Apple example of the familiarity bias when an iMac is powered on

Tips Familiarity bias.

  1. Borrow Design Elements. Incorporate well-known icons and symbols in your site's navigation which users are already familiar with, like home, search, or user profile.
  2. Use Common Fonts. Always opt for easy-to-read fonts that users encounter frequently, enhancing readability and thus, their comfort level.
  3. Consistent Layout. Maintain a consistent layout across your website. Users become familiar with your design quickly and navigate more intuitively.

Hindsight bias.

People tend to overestimate their ability to predict the outcome of an unpredictable event as if it were easily foreseeable.


Definition Hindsight bias.

You know that feeling when you watch a sports game and think, "I knew they would win!" even though you were biting your nails the whole time?

That's Hindsight Bias in action.

Why does it work? It's rooted in our need to find order in the world and believe in our own predictive powers.

It's that "I knew it would happen" feeling we get after the fact, making us believe we predicted or expected an outcome that was actually uncertain.

Websites and brands can use this bias to their advantage, especially when it comes to user engagement and decision-making.

When users feel like they "knew" they were making the right choices all along, it boosts their confidence and trust in your platform, encouraging further interaction.

Examples Hindsight bias.


Ever start typing and Google instantly suggests the exact thing you were looking for?

It's not just helpful; it makes you feel like a genius.

You think, "I was just about to type that!".

This boosts your confidence and makes you feel smarter, reinforcing your trust in Google's platform.

Google's automatic suggestions as an example of the hindsight bias

You make a purchase, and Amazon immediately suggests items that perfectly complement what you just bought.

You can't help but think, "Wow, I was going to search for that next!".

It's like Amazon read your mind, making you feel smarter and more inclined to make another purchase.

The example of Amazon's related items suggestions

Grammarly uses predictive pop-ups to guide user actions.

Imagine you're typing an email and suddenly a pop-up appears suggesting a more effective way to phrase your sentence.

You think, "Ah, I was just about to rephrase that!".

Grammarly isn't just correcting your grammar; it's making you feel like a linguistic genius.

You were "about to make that change anyway," and Grammarly just confirmed your brilliance.

This predictive guidance makes users feel smarter and more in tune with the tool, increasing the likelihood that they'll continue using it for all their writing needs.

The Grammarly example of the hindsight bias

Tips Hindsight bias.

  1. Run A/B Test. Running A/B Tests can mitigate hindsight bias. By comparing different versions of your pages, you can make accurate updates based on quantifiable data, not post-event intuition.
  2. Personalize User Experience. Users feel smarter when they see "handpicked" product recommendations. Cater to the hindsight bias by creating a personalized experience that resonates with their prior knowledge.
  3. Leverage Predictive Pop-ups. Use predictive pop-up messages to guide users’ actions. It will make the users believe they were anticipating the step, making the experience feel intuitive and personal.

Halo effect.

Refers to the tendency to let our overall impression of a person, company or product positively influence our judgment of its other traits.


Definition Halo effect.

The halo effect is a cognitive bias in which our general impression of a person influences the way we feel and think about their personality.

Examples Halo effect.


Our general impression of celebrities is an excellent example of the halo effect in action.

Indeed, since people perceive them as attractive, talented and often likeable, they also tend to regard them as intelligent, caring and funny.

These considerations can spill over into a product or service that a celebrity presents by association.

An excellent example is James Bond and how Aston Martin quickly became the secret agent's iconic car (agent 107).


Tips Halo effect.

  • Make sure you dress well. Numerous studies have shown that dressing well has a considerable impact on a person's perceived attractiveness.
  • Pay attention to your body language and what you're wearing.


People value things more when they are rare, in limited quantities.


Definition Scarcity.

The scarcity effect is the cognitive bias that causes people to place a higher value on a rare object and a lower value on one that is abundantly available.

Scarcity is associated in our brains with something positive, luxurious and exclusive, because we automatically assume that an object is rare because everyone wants it or has already bought it, and that it is therefore a good product.

In other words, rare objects arouse our interest and therefore become immediately more desirable than a readily available product.

Examples Scarcity.


Booking.com is a master of scarcity marketing. Watch how they imply that this hotel offer won't be available for much longer.

Be warned, scarcity should be used in moderation and, with real data, can encourage users to take action more quickly on your site.

However, this technique has been adopted (and abused) by so many sites that its impact can vary.

Therefore, it's best to test which type of scarcity works best with your business and when.


Tips Scarcity.

  • By displaying the number of items remaining in stock, you can encourage people to make their purchase more quickly out of fear that the item may no longer be available.
  • By displaying the words “Only available online”, visitors are encouraged to make purchases, as the products seem rarer, being only available online.
  • Indicate whether certain variants of your product are out of stock to increase rarity.


People tend to return favors given to them.


Definition Reciprocity.

Reciprocity is that innate human urge to give back when we've received.

In web design, offering users something valuable–like a free guide, can prompt reciprocation – users may provide contact information or make a purchase.

Why does this work? Because we're wired to balance the scales. When someone does us a favor, we instinctively want to return it. It's a dance as old as time, and it's deeply ingrained in our psyche.

Examples Reciprocity.


Picture this: You're walking past a bustling coffee shop. The aroma is inviting, but you're in two minds about stopping.

Just then, an employee offers you a small cup - a sample of their new seasonal blend. You take a sip, and it's delightful.

Now, you're considering a purchase, and not only because you think it tastes good.

Why then? Because they gave you something for free, and now you want to reciprocate.

It's not just about giving away a sample; it's about creating a sense of indebtedness, a desire to give back.

An example of the reciprocity bias when a free sample of coffee is given to you

HubSpot offers a plethora of free educational resources, from detailed blog posts to comprehensive webinars and even certifications.

Users can access a wealth of knowledge without spending a dime.

In return, many users feel inclined to explore HubSpot's paid offerings, having already benefited from the company's free content.

It's a digital give-and-take, with HubSpot providing value upfront.

Huspot's free resources as an example for the reciprocity bias

Dropbox has this "Share and Earn" approach where they reward both the existing user and the new user invited through their referral program.

When you invite a friend to join Dropbox, and they install and log into the Dropbox desktop app, both you and your friend earn extra storage space.

This is a powerful form of reciprocity.

By offering tangible value (extra storage), Dropbox encourages users not only to engage more with their service but also to become active promoters of their brand.

Dropbox's "Share and Earn" approach as an example of reciprocity

Tips Reciprocity.

  1. Give your users gifts. Offer visitors a free e-book, guide, or sample. This provides immediate value and may encourage them to return the favor (by subscribing or buying).
  2. Share valuable content. Blog posts that deliver in-depth insights, industry news, or how-tos are free gifts. The higher their quality, the more likely your visitors will repay with loyalty.
  3. Provide an exceptional customer service. Going the extra mile in providing assistance can lead to positive feedback and recommendations. It’s a sign of respect that invites reciprocation.

Social proof.

Users adapt their behavior according to what others are doing, in order to be liked, resemble or be accepted by society.


Definition Social proof.

Social proof, theorized by psychologist Robert Cialdini, holds that a person who doesn't know what the appropriate behavior is in a certain situation will look to other people to imitate what they're doing, and thus guide his or her actions. The greater the number of people involved, the more appropriate the action will seem.

So, in situations where we don't know what to do, we assume that the people around us (experts, celebrities, friends, etc.) have better knowledge of what's going on and what to do.

Examples Social proof.


What's more, we often make judgments based on the general impression we have of someone: this is the halo effect (named by psychologist Edward Thorndike). For example:

  • We think everything the experts use is great because they're probably more knowledgeable than we are in their field of expertise.
  • We buy products endorsed by celebrities because we want to be like them (or just have their freedom).
  • We trust customer reviews because they've experienced the product or service, unlike us.

One of the best examples of social proof, in real life, is the long queue outside an Apple Store on the day a new iPhone is released.

The fact that a group of people find the new phone so desirable that they spend a considerable amount of time queuing has an impact on our perception of the phone's perceived value (and drives us to covet one too).

Exemple de preuve sociale avec la sortie d'un nouvel iPhone

A similar example is the queue outside a restaurant.

Indeed, it's important for businesses to show that they're busy, which is why restaurants and bars often make sure there's a queue outside the entrance. Websites do the same, but with different strategies.


Tips Social proof.

  • Getting experts in your sector to speak out on your social networks can be an excellent way of exploiting their influence and the positive association they have in your industry (also: halo effect and authority bias).
  • From time to time, you may receive a nice mention from the press, a major brand or an influencer in your sector. This is an exceptional form of social proof to share.
  • User-generated content is a critically important strategy for generating social proof and building community.

Unit bias.

Tendency to finish a whole 'unit’ simply because it's presented as a whole.


Definition Unit bias.

Ever find yourself eating just one more chip because the bag's almost empty? That's Unit Bias.

You want to finish what you started.

In other words, it's the tendency for humans to want to complete a single unit of a task or item.

On websites, a visual indicator of progress can enhance user experience, helping users feel accomplished.

Now, let's see how brands use this to keep you clicking.

Examples Unit bias.


Amazon’s "Customers Also Bought" and "Frequently Bought Together" sections are perfect examples of unit bias in action.

When purchasing a book, you might see a recommendation to buy the whole trilogy, or a book and its movie adaptation all at once.

We're biased to perceive the recommended set of items as a single unit, making us more likely to purchase the whole bundle – even if we initially intended to buy just one item.

Amazon as an example of the unit bias

Netflix cleverly uses the principle of unit bias to increase viewership.

When you finish watching an episode of a series, Netflix automatically queues up the next episode.

This positions each TV show as a unit, subtly encouraging viewers to watch more.

The countdown timer before the next episode starts playing is relatively short, about a few seconds, making it more likely for people to continue watching the next episode even if they had only intended to watch one.

Example of the unit bias with Netflix

"You're 90% Complete"

LinkedIn nudges you to complete your profile by showing a “Profile Strength” meter.

You've already added your experience and skills. Why not add that recommendation to hit “All-Star” status?

Completing your profile is presented to you as one single unit, so that you are more likely to complete it.

Note that this feature also leverages Commitment and Consistency Bias.

Once you've started building your profile, you feel an internal pressure to be consistent with the decision to have a LinkedIn profile.

Linkedin "profile strength" meter as an example of the unit bias.

Tips Unit bias.

  1. Limit Options. Present users with smaller choice counts. Offering less can boost engagement, as users may become overwhelmed by too many options.
  2. Tier Your Offerings. Use unit bias to promote higher-priced items. Bundle products or services into packages and distinguish each by emphasizing the value added.
  3. Use a Default. Set a favorable option as default. Users are more likely to stick with the initial choice, improving chances for desired user behavior.


When users know what to expect before taking action.


Definition Feedforward.

Examples Feedforward.


Tips Feedforward.


Goal-Gradient Effect.

As users get closer to a goal, their motivation increases to reach it faster.


Definition Goal-Gradient Effect.

Examples Goal-Gradient Effect.


Tips Goal-Gradient Effect.


Aha! moment.

The moment when users first experience the added value of your product and the benefits it brings to their lives.


Definition Aha! moment.

Examples Aha! moment.


Tips Aha! moment.



Users adapt more easily to things that are similar to real-life objects in appearance and/or in the way they can interact with them.


Definition Skeuomorphism.

Examples Skeuomorphism.


Tips Skeuomorphism.


Law of Prägnanz.

Users perceive and interpret ambiguous or complex images in the simplest possible way, as this requires less mental effort.


Definition Law of Prägnanz.

Examples Law of Prägnanz.


Tips Law of Prägnanz.


Authority bias.

Users tend to attribute greater importance and accuracy to the opinion of an authority figure.


Definition Authority bias.

Examples Authority bias.


Tips Authority bias.


Survey Bias.

Users tend to orient survey responses towards what is socially acceptable.


Definition Survey Bias.

Examples Survey Bias.


Tips Survey Bias.


Cheerleader effect.

People think that individuals or products are more attractive when presented as a group.


Definition Cheerleader effect.

Examples Cheerleader effect.


Tips Cheerleader effect.


Law of Similarity.

The human eye tends to perceive a relationship between similar elements.


Definition Law of Similarity.

Examples Law of Similarity.


Tips Law of Similarity.


Fresh Start Effect.

Users tend to take initiative to achieve a goal if there's a sense of a new beginning.


Definition Fresh Start Effect.

Examples Fresh Start Effect.


Tips Fresh Start Effect.


Spotlight effect.

People tend to overestimate the amount of attention others pay them than they actually get.


Definition Spotlight effect.

Examples Spotlight effect.


Tips Spotlight effect.


Singularity Effect.

How users are disproportionately interested in an individual versus a group.


Definition Singularity Effect.

Examples Singularity Effect.


Tips Singularity Effect.


Streisand Effect.

Attempts to conceal, suppress or censor information, when these efforts instead lead to increased awareness.


Definition Streisand Effect.

Examples Streisand Effect.


Tips Streisand Effect.


Eureka effect.

When new users become aware of the benefits of using your product for the first time.


Definition Eureka effect.

Examples Eureka effect.


Tips Eureka effect.


Noble Edge Effect.

Users tend to prefer socially responsible companies and perceive them as more authentic.


Definition Noble Edge Effect.

Examples Noble Edge Effect.


Tips Noble Edge Effect.


Curse of knowledge.

People unknowingly assume that the other person has the same level of knowledge.


Definition Curse of knowledge.

Examples Curse of knowledge.


Tips Curse of knowledge.


Miller's Law.

On average, a user can only keep 7±2 items in their working memory.


Definition Miller's Law.

Examples Miller's Law.


Tips Miller's Law.


Self-Initiated Triggers.

Users are more likely to interact with messages they have created themselves.


Definition Self-Initiated Triggers.

Examples Self-Initiated Triggers.


Tips Self-Initiated Triggers.


Variable reward.

People appreciate rewards much more when there's an element of randomness.


Definition Variable reward.

Examples Variable reward.


Tips Variable reward.


Pseudo-Set Framing.

Tasks that are part of a whole are more exciting to accomplish.


Definition Pseudo-Set Framing.

Examples Pseudo-Set Framing.


Tips Pseudo-Set Framing.


Flow state.

Flow is a state of mind in which a person is completely immersed in an activity and their concentration is at its highest.


Definition Flow state.

Examples Flow state.


Tips Flow state.


Curiosity Gap.

Users have a strong desire to find missing information.


Definition Curiosity Gap.

Examples Curiosity Gap.


Tips Curiosity Gap.


Cognitive dissonance.

Used to describe the mental discomfort resulting from the existence of two contradictory ideas in an individual's mind.


Definition Cognitive dissonance.

Examples Cognitive dissonance.


Tips Cognitive dissonance.


Hawthorne Effect.

Tendency of user to alter their usual behavior when they know they're being watched.


Definition Hawthorne Effect.

Examples Hawthorne Effect.


Tips Hawthorne Effect.


Occam's razor.

Users consider that simple solutions are often better than more complex ones.


Definition Occam's razor.

Examples Occam's razor.


Tips Occam's razor.

⏰ Act within a given time.

Users are often called upon, so they look for shortcuts
and quickly draw conclusions.


Sunk Cost Effect.

Spending more because you've already invested time and effort, even if it doesn't make sense.


Definition Sunk Cost Effect.

Ever found yourself watching a show only because you’ve already invested time in the first few episodes, even if it’s not that great?

That's the Sunk Cost Effect, where individuals continue an endeavor once an investment (time, money, effort) has been made.

You might think it's similar to the Commitment and Consistency Bias and you are right, it's connected.

While both biases result in individuals being hesitant to abandon an initiated action, the roots of this reluctance differ.

The Commitment and Consistency Bias stems from a desire to remain aligned with previous commitments, as discontinuation would result in Cognitive Dissonance.

Whereas the Sunk Cost Effect arises from an unwillingness to forfeit invested resources, making discontinuation feel like a loss.

Examples Sunk Cost Effect.


A typical example of this dynamic is in online gaming platforms.

Users initially make small commitments like creating characters, embodying Commitment & Consistency Bias.

These small commitments draw the player into the game world, establishing a basic level of engagement and investment.

As they invest time and money, accumulating assets and achievements, walking away becomes difficult due to the Sunk Cost Effect.

The more they invest, the harder it becomes to simply walk away from the game, as they would lose all the progress and assets they've accumulated.

Game designers in this case leverage both biases to attract and retain players.

The Sims Freeplay as an example of the sunk cost effect

Think of the subscription model of Spotify.

Once a user has paid for a premium account, they want to get their money's worth, making them more likely to use the service regularly.

They might even prefer Spotify over free alternatives because they've sunk cost into it.

Moreover, users are less likely to cancel their premium account even when they don’t use Spotify extensively.

It nudges them to keep the subscription to justify the initial cost, benefiting Spotify with recurring revenue.

Spotify example for the sunk cost effect

After opting for LinkedIn Premium for a job search, users tend to stay subscribed.

They aim to leverage the advanced features they’ve paid for, even if they might not need them as much after securing a job.

Linkedin premium as an example of the sunk cost effect

Tips Sunk Cost Effect.

  1. Leverage the Commitment and Consistency Bias. Introduce a progress bar for tasks, highlighting sunk costs and boosting users' drive to finish what they started, subtly initiating a commitment.
  2. Create Reward Systems. Implement reward or loyalty programs where users accumulate points or status, making them more likely to stick around to enjoy the benefits of their earned rewards.
  3. Offer free trials. After investing time, users are inclined to purchase to validate their investment. Introduce paid or premium features that offer value, enticing users to invest and continue using your service to maximize their purchase.

The Labor Illusion.

People value a product more when they see the work that has gone on behind the scenes.


Definition The Labor Illusion.

The Labor Illusion means that consumers perceive good products more favorably when they are aware of the effort involved.

Making users wait for a product they've requested while showing them how it's prepared gives the impression of effort. Customers are then more likely to appreciate the results of this effort.

This is also known as the “KAYAK effect” (after the travel booking site that used this tactic).

Examples The Labor Illusion.


KAYAK (travel booking site) once delayed the loading time of the search results page to show that it: actively seeks the best results.

Exemple du labor illusion avec le site de vouyage Kayak.com

Starbucks now requires baristas to steam milk for each individual drink – a process that increases waiting time, but allows customers to see what's going on.


Tips The Labor Illusion.

  • Show that you're working. But time and effort aren't the only factors involved. Transparency is essential: consumers need to know that effort is being made on your part.
  • You can show the work behind your product or service by demonstrating the process it requires, while also showing what goes on behind the scenes.

Ikea effect.

People tend to appreciate an object more if they make (or assemble) it themselves.


Definition Ikea effect.

The IKEA effect, named after the Swedish furniture giant, describes how people tend to appreciate an object more if they make (or assemble) it themselves.

More generally, the IKEA effect shows that we tend to appreciate objects more if we've put some effort into creating them.

Examples Ikea effect.


Two groups received IKEA boxes, one fully assembled and the other unassembled, which they had to assemble. Members of the second group were willing to pay significantly more for their boxes than those who had received their pre-assembled boxes.

The above experiment was conducted by Michael I. Norton of Harvard Business School, Daniel Mochon of Yale and Dan Ariely of Duke.


Companies that sell services that facilitate creativity, benefit the most.

For example, Canva, a graphic design tool, offers its users tons of templates, photos, illustrations and fonts that let them bring their creativity to life.


Tips Ikea effect.

  • Please note that the IKEA effect only occurs if the object is successfully assembled. If people fail to build a product according to the instructions provided, the value they attribute to it does not increase - quite the contrary.

Fear of missing out.

Fear of Missing Out (FOMO) is the constant fear people have of missing an important news or event.


Definition Fear of missing out.

Fear of Missing Out (FOMO) is a design principle leveraging users' anxiety of not being part of an interesting, rewarding experience others are having.

Now, how does this work? Our brains are wired to avoid regret.

We don't want to miss opportunities. Brands tap into this by creating limited-time offers, exclusive deals, or showcasing low stock alerts.

By invoking a sense of urgency with fleeting opportunities, users are nudged towards immediate action.

Examples Fear of missing out.


Amazon’s annual Prime Day provides a prime example of the Fear of Missing Out (FOMO) design principle.

During this limited-time event, exclusive deals for Prime members are advertised with a countdown timer showing how much time is left to snag the offer.

The knowledge that these deals are fleeting creates a sense of urgency and scarcity, driving shoppers to make impulse buys they might otherwise mull over.

With the added element of competition - the awareness that other shoppers might beat you to checkout - Prime Day effectively utilizes FOMO to boost sales.

An example of the Fear of Missing Out Bias with Amazon Prime Day

When you're browsing accommodations on Booking.com, you'll often see a notification stating something like "only 6 left for this price", "10 people are looking at this

property right now", or even the percentages of places to stay unavailable for the dates you have picked.

An example of the Fear of Missing Out bias with Booking.com

The underlying message is clear: if you don't act fast, you might miss out on your preferred accommodation.

This isn't just about the property's popularity; it's about the potential fear and negative experience of not securing your desired stay.

Remember that negative feelings of disappointment are powerful and linger in our memories.


Picture this: You're scrolling through your favorite online store - let's say Asos - and you spot a pair of shoes you've been eyeing for weeks.

But just when you pick your size, a tiny notification pops up: "Low in stock"

Your heart races. You don't want to miss out. So, without a second thought, you buy them.

An example of the Fear of Missing Out bias with Asos

In this case, we're more driven to avoid negative experiences. Why?

It's not that we're pessimistic by nature; it's just that potential negative outcomes have a more significant impact on our psyche and decision-making processes.

Tips Fear of missing out.

  1. Use Limited Time Offers. Create promotions that are time-bound to create urgency. Ensure the timer is visibly ticking down on your site so your customers know they have limited time to act.
  2. Create Flash Sales. Use flash sales to keep your users engaged and excited. Alert them prior to the sale and let them know the window of opportunity is brief.  
  3. Show Limited Stock. Indicate items are in high demand and low in stock. This creates a sense of scarcity and propels users to act quickly to avoid missing out.

Commitment & Consistency.

Once we choose a path, we're likely to stick with it.


Definition Commitment & Consistency.

Commitment & Consistency is a design principle rooted in people's desire to be consistent with past actions.

In web design, it's easier to ask users to make a small commitment (like signing up), making them more likely to engage in more demanding tasks (like buying a product).

But why does it work? It's tied to our self-image and the human need for coherence.

When we commit to something, even in a small way, it becomes part of how we see ourselves.

Acting in a manner consistent with that commitment reinforces our self-perception and reduces cognitive dissonance.

Examples Commitment & Consistency.


Look at LinkedIn's profile completion bar - a brilliant use of commitment and consistency.

When you start creating your profile, LinkedIn gives you a "completeness score" and provides clear, easy steps to achieve 100%.

Users are more likely to stick around, building a complete, professional profile, because they’ve already started the process.

This nudges members to commit to using the platform regularly, increasing user engagement and retention.

Note that this "completeness score" also taps into the Unit Bias.

You're more likely to complete your profile because the partial score nudges you to finish the "unit" you started.

LinkedIn example of commitment and consistency

Duolingo uses the commitment and consistency principle in its user experience design.

Once you start using Duolingo, you're asked to set a daily goal for language practice.

Whether it's 5 minutes or 20 minutes a day, the app encourages regular learning behavior.

The user also receives encouraging notifications and streak counts that reward consistency, inherently motivating the user to meet their daily goal.

If you miss a day, the streak resets, creating a sense of loss and motivating the user to keep the streak alive.

Learners made a small commitment by starting the process, making them more likely to continue regular use of the app.

Duolingo example of the consistency and commitment bias

Let's imagine you decided to buy the new iPhone 15.

An example of commitment and consistency bias with Apple's checkout process

After committing to buy an iPhone, Apple's checkout process offers Apple Care and accessories.

This is cross-selling, smartly leveraging Commitment and Consistency Bias to encourage adding these extras, consistent with the initial iPhone purchase.

An example of commitment and consistency bias with Apple's checkout process

The Apple Care option only appears after you've added the iPhone, and the lower-priced accessories act as a price anchor.

Because you've already committed to the iPhone, you're psychologically wired to stay consistent with that choice.

An example of commitment and consistency bias with Apple's checkout process

Tips Commitment & Consistency.

  1. Start your user's journey with easy choices. Initial low-stakes commitments foster rapport and confidence, paving the way for more significant actions later.
  2. Regularly solicit user input. Engaging users in polls or surveys promotes continuous engagement, nudging them to stay consistent with their commitments.
  3. Use persistent design elements. Consistent color themes, typography, and layout across your website helps establish familiarity and reliability, aiding solid commitment from the user.

Investment loops.

When users invest in something, they're more likely to come back.


Definition Investment loops.

Ever noticed how the more you invest time and effort into something, the more attached you become?

It's like tending to a plant.

The more you water and care for it, the more you want to see it flourish.

This design principle capitalizes on the idea that the more users invest time, effort, or even money into a product or service, the more they value it and the more likely they are to continue using it.

Why does it work?

Because humans inherently value things more when they've put effort into them. It's a cycle: invest, see the value, invest more.

Examples Investment loops.


Ever tried learning a language on Duolingo?

The more lessons you complete, the longer your streak becomes.

And the longer your streak, the more you want to keep it going.

You've invested time daily, and now you're not just learning a language; you're maintaining a record.

Duolingo brilliantly leverages this investment loop to keep users coming back every day.

Duolingo's streak as an example of investment loops

Note that this also taps into the Commitment and Consistency Bias.

Once users commit to a daily learning habit, they strive to stay consistent with that commitment, further driving engagement.


Consider apps like MyFitnessPal or Fitbit.

The more you log your meals, workouts, or steps, the more data you have on your fitness journey.

This investment of time and effort makes you more committed to the app and your health goals.

You've built a history, and now you're more motivated to continue and see further progress.

MtFitnessPal App as an example of the investment loops bias

Ever signed up for a content platform and been prompted to select your interests?

Take Medium for example. It feels like setting up your own personalized magazine.

From that moment, Medium begins to curate a feed tailored just for you.

Every article you read and every topic you select further refines this feed.

The more you engage, the richer your experience becomes.

This initial investment in setting up your preferences ensures you're more committed to returning and diving deeper into the content.

Medium's clap feature as an example of the investment loops bias

Tips Investment loops.

  1. Create game-like progress. Turn tasks on your site into challenges or stages. Users feel they're achieving something, boosting return rates and experiences.
  2. Incentivize involvement. Reward users for frequent visits or referrals. It fuels both their investment and boosts site interaction.
  3. Personalize the journey. Let users customize profiles or set preferences. They'll feel an attachment thus, revisiting to maintain their investment.

Decision Fatigue.

Making a large number of decisions requires a great deal of mental effort, which reduces users' ability to make rational choices.


Definition Decision Fatigue.

Decision fatigue describes situations where we are making decisions, our remaining mental energy is diminishing, because the more decisions we make, the more mental fatigue we feel, and this affects everyone, including your customers.

Decision fatigue is the reason we feel overwhelmed when we have too many choices to make.

Examples Decision Fatigue.


Let's take the example of e-commerce sites, especially those with product sheets featuring numerous variations on the same product.

Instead of increasing conversion rates by offering your users a multitude of choices, you're actually discouraging them from taking action by offering them an abundance of choices.

So avoid adding a dozen variants to a single product.

Less is more. Or simply find a good way of presenting these variants:


Tips Decision Fatigue.

  • Facilitate your users' experience with a conversion-optimized web design that guides your users directly to your call to action.
  • Don't overwhelm your customers with information, long texts and calls to action galore.

Loss aversion.

People prefer to avoid the pain of losing, as it is psychologically twice as important as the pleasure of winning equivalent gains.


Definition Loss aversion.

Loss aversion is a cognitive bias that describes why, for individuals, the pain of losing is psychologically twice as strong as the pleasure of winning.

In other words, losing €1,000 will "hurt" more than the satisfaction of winning €1,000.

Examples Loss aversion.


Insurance companies try to attract new customers by showing the many potential and costly losses an individual may suffer in his or her lifetime.

To avoid these losses, an individual would prefer to pay low ongoing costs, which is the case with most insurance companies and their business models.


Tips Loss aversion.

  • Formulate your offer in terms of loss. Make it risky. Offer a reference point for comparison.
  • Inspire the "fear" of losing a unique offer. Be definitive, setting a deadline. Be precise, stating a clear loss.

Status Quo bias.

People tend to stick with what they know and resist change.


Definition Status Quo bias.

Status Quo Bias in design refers to users' natural resistance to change.

Picture it as that cozy blanket of comfort we wrap ourselves in, preferring to keep things just the way they are.

In the digital realm, it's about understanding that users often lean towards familiar choices, resisting change even if a new option might be beneficial.

But here's the twist: change isn't the enemy. The challenge lies in how it's introduced.

Users can embrace change when it's presented as a clear upgrade to their experience or if it's subtile.

Examples Status Quo bias.


Think of Amazon Prime. Users quickly adapt, enjoying the convenience and benefits.

But here's the catch: once the trial ends, they're automatically rolled into a paid subscription.

Why does this work? Why most people do not cancel the subscription?

Because by then, Amazon has made us accustomed to a superior experience, a better status quo.

The thought of reverting to a world without those perks feels like a step backward.

Amazon capitalizes on our natural resistance to change, our tendency to stick with the default, and the effort required to change it.

Note that Amazon show a great understanding of another biases: the Reciprocity Bias.


Think about the last time Apple rolled out an iOS update.

Icons, layouts, and core functionalities - they're tweaked but not overhauled.

That's not by accident. Apple isn't just updating; they're carefully maintaining your personal "status quo."

Why? Apple knows the importance of the Status Quo Bias.

Any shift or replacement in functionality isn't just for the sake of change; it's always a trade-up for better.

It's like moving into a renovated house but finding your favorite couch still in the living room, offering that reassuring continuity.

The apple updates as an example for the status quo bias

It's Friday night, and you're diving into your Netflix account, ready for a movie marathon.

But with a world of choices, where do you even begin? Here's where Netflix plays it smart.

Instead of pushing the newest or most popular titles on you, they gently steer you with "Because You Watched" lists.

It feels like Netflix is saying, "You enjoyed this before, so why change the rhythm now?"

They're not just catering to your tastes; they're acknowledging your preference to stick with what's familiar.

By doing so, they're tapping into our inherent resistance to change, our comfort in the known.

Note that Netflix's strategy is a masterclass in combining the Status Quo Bias with a deep understanding of the Familiarity Bias, making our viewing choices both comforting and intuitive.

An example of the status quo bias with Netflix

Tips Status Quo bias.

  1. Give them the choice. Give your users the option of sticking with the default settings. They are more likely to leave them untouched, so use that to guide their experience favorably.
  2. Set up auto-renew plans for your offerings. Humans naturally prefer to keep things the same so users are less likely to cancel a recurring plan.
  3. Do minor, justified and valuable changes. When redesigning your web interface, keep core components familiar. Abrupt changes can cause disarray. Ease users into new designs to encourage retention. Show users the tangible benefits of the change.

Dunning-Kruger effect.

People tend to overestimate their skills when they have limited knowledge in a field.


Definition Dunning-Kruger effect.

Examples Dunning-Kruger effect.


Tips Dunning-Kruger effect.


Barnum effect.

Describes the case where individuals believe that generic information, which could apply to anyone, applies specifically to themselves.


Definition Barnum effect.

Examples Barnum effect.


Tips Barnum effect.


Affect heuristics.

People often rely on their emotions, rather than factual information, to make decisions.


Definition Affect heuristics.

Examples Affect heuristics.


Tips Affect heuristics.


Belief perseverance.

When people's beliefs are challenged by evidence to the contrary, their beliefs are reinforced.


Definition Belief perseverance.

Examples Belief perseverance.


Tips Belief perseverance.



Users are less likely to adopt a behavior when they feel forced.


Definition Reactance.

Examples Reactance.


Tips Reactance.


Bandwagon effect.

Tendency to adopt specific behaviors, styles or attitudes simply because others do.


Definition Bandwagon effect.

Examples Bandwagon effect.


Tips Bandwagon effect.


Weber's Law.

Users adapt better to small, gradual changes than to a complete overhaul.


Definition Weber's Law.

Examples Weber's Law.


Tips Weber's Law.


Self-serving bias.

The tendency to attribute positive events to oneself, but to attribute negative results to external factors unrelated to oneself.


Definition Self-serving bias.

Examples Self-serving bias.


Tips Self-serving bias.



People perceive time subjectively.


Definition Chronoception.

Examples Chronoception.


Tips Chronoception.



The ease with which users can discover your features.


Definition Discoverability.

Examples Discoverability.


Tips Discoverability.


Hyperbolic Discounting.

People tend to choose immediate rewards over future rewards, even if those immediate rewards are less important.


Definition Hyperbolic Discounting.

Examples Hyperbolic Discounting.


Tips Hyperbolic Discounting.


Planning Fallacy.

People underestimate the time needed to complete a task, as well as the associated costs and risks, even if this contradicts their own experiences.


Definition Planning Fallacy.

Examples Planning Fallacy.


Tips Planning Fallacy.

Parkinson's law.

People will continue to work on a task until their allotted time is reached.


Definition Parkinson's law.

Examples Parkinson's law.


Tips Parkinson's law.


Observer-expectancy effect.

Refers to the way in which a researcher's expectations can influence those being observed.


Definition Observer-expectancy effect.

Examples Observer-expectancy effect.


Tips Observer-expectancy effect.


Cashless Effect.

People tend to be more inclined to spend when there's no physical money involved in a transaction.


Definition Cashless Effect.

Examples Cashless Effect.


Tips Cashless Effect.


Temptation Coupling.

Difficult tasks are less frightening when they're associated with something users want.


Definition Temptation Coupling.

Examples Temptation Coupling.


Tips Temptation Coupling.


Law of the instrument.

When people acquire a new skill, they tend to see opportunities to use it everywhere.


Definition Law of the instrument.

Examples Law of the instrument.


Tips Law of the instrument.


False consensus effect.

People overestimate and assume that their own opinions are more widely shared than they actually are.


Definition False consensus effect.

Examples False consensus effect.


Tips False consensus effect.


Dark Pattern.

These are deceptive UX/UI interactions, designed to trick users into doing something they don't want to do.


Definition Dark Pattern.

Examples Dark Pattern.


Tips Dark Pattern.


Second-Order Effect.

Each action leads to a consequence, and each consequence follows another.


Definition Second-Order Effect.

Examples Second-Order Effect.


Tips Second-Order Effect.


Pareto Principle.

80% of the results are the fruit of 20% of the actions implemented.


Definition Pareto Principle.

Examples Pareto Principle.


Tips Pareto Principle.

💾 Store interaction in memory.

Users try to remember what's most important, but their brain prioritizes
certain elements over others.



People retain more information when it's grouped together.


Definition Chunking.

Chunking is a design principle that involves breaking information into manageable “chunks” or sections, making it easier for users to process and remember.

This technique reduces cognitive load, enhancing user experience by presenting information in a way that aligns with how the human brain works.

Why does it work?

Chunking works because the human working memory can only hold a limited amount of information at once.

By organizing data into smaller units, users can more easily understand, remember, and interact with the information presented.

Examples Chunking.


When you first visit YouTube, videos are organized into various categories or “chunks” like "Trending", "Music", or "Gaming".

This chunking of content allows users to easily navigate without feeling overwhelmed by the vast amount of content available.

Users can quickly identify and choose the category that interests them, making the browsing experience more enjoyable and efficient.

Youtube's homepage example for chunking

Online stores often use chunking in product categories.

For instance, Amazon organizes millions of products into broader categories like "Electronics", "Books", or "Clothing".

Within each, there are sub-categories, further chunking information to aid user navigation.

This structure simplifies the search process for users, allowing them to find products faster and with less cognitive effort.

Example of chunking with Amazon

In real life, when learning a language, we naturally break down information into smaller units, due to our brain's limited capacity.

This step-by-step approach makes the process less overwhelming and aids in better retention and understanding.

Online learning platforms like Duolingo emulate this natural learning process.

Once you start using Duolingo, you're asked to set a daily goal for language practice.

They employ chunking by dividing lessons into bite-sized sections, making the learning process appear more achievable for users.

Note Duolingo also leverages the Commitment and Consistency Bias with its streak system.

An example of chunking with Duolingo

Tips Chunking.

  1. Break Down Information. Translate big, confusing data into "bite-sized" pieces. Short paragraphs, bullet points, and numbered lists make complex concepts more digestible.
  2. Use Headers/Sub Headers. Divide your content with clear, distinct headers. These act as guideposts and help readers find specific information quickly.
  3. Group Related Ideas. Put similar ideas, like product features or team bios, together. This helps readers make connections faster and improves memory recall.

Endowment effect.

Users value something more if they feel it belongs to them.


Definition Endowment effect.

The endowment effect describes how people tend to place more value on goods they own than those they don't.

Users are more likely to want to keep something they already own than to acquire it again.

They tend to overvalue the things they own, whatever their objective market value. (cf. Loss aversion)

Examples Endowment effect.


For example, Shopify offers a blog and free guides, all designed to help customers develop their e-commerce store.

Offering a free trial, as Shopify does, also leverages the endowment effect, especially if users are encouraged to create their own store during the 14-day trial.


The Apple showroom allows visitors to touch and use all the products without time limit.

Staff are asked not to pressure visitors to leave, and the showroom itself is open and welcoming to reinforce the sense of belonging.


Tips Endowment effect.

  • Letting your customers use your products or services is a great way to trigger the endowment effect.
  • Free trials are one thing, but offering a freemium version of your products is a great way to give people ownership and trigger the endowment effect.

Zeigarnik effect.

People tend to remember interrupted or incomplete tasks or events more easily than completed ones.


Definition Zeigarnik effect.

Have you ever found yourself thinking about a partially completed school or work project while trying to concentrate on something else? Or perhaps you've wondered what's going to happen next in your favorite soap opera?

If so, you've experienced the Zeigarnik effect, the tendency to remember unfinished tasks better than completed ones.

According to Lewin's theory, a task in progress creates task-specific tension. This tension subsides when the task is completed.

But if the task is interrupted, any reduction in tension is impeded. With permanent tension, relevant information becomes more accessible and easier to remember.

Examples Zeigarnik effect.


Marketers often use progress bars for forms or checkout processes.

This bar reminds users where they are in the process and motivates them to complete the action.

The effect is often enhanced if the bar is already in the middle of the process when it first appears, making the user feel more involved.


LinkedIn is quite famous for using this technique. Instead of presenting users with a long, overwhelming list of questions, it simply asks them to sign up first, then collect information later, in a very clever way.


Showing a progression and a list of tasks to complete is a common practice to motivate players to immerse themselves in games.
But it's also a widely used and motivating practice found in language learning applications: gamification.

Tips Zeigarnik effect.

  • Providing a progression towards a goal ensures that users are more likely to be motivated to complete the task.

Negativity bias.

People recall bad experiences better than good ones.


Definition Negativity bias.

Negativity bias is a tendency of users to give more importance to negative experiences over neutral or positive ones.

Sometimes people are even more curious about the negative details.

Why? It's evolutionary - our ancestors needed to remember threats to survive.

Picture it as the reason why you remember that one negative comment on your post despite the 99 positive ones.

Examples Negativity bias.


Turn on the news on any given day, and you're likely to be met with a barrage of headlines highlighting crises, controversies, and calamities, all negative news.

But is the world truly as bleak as the news portrays, or is something else at play?

News media are a great example of negativity bias

The media understands that negative stories capture attention.

This isn't because positive events are less newsworthy, but because negative events evoke stronger emotional reactions, making them more memorable and shareable.


Insurance companies often spotlight potential disasters in their ads: homes ravaged by storms, accidents without coverage, or even a bear attack on your car.

This strategy taps into our negativity bias, and it simultaneously plays on loss aversion, which refers to our innate desire to avoid losses rather than acquiring gains.

Note that both principles are connected.

Consider the Allstate's "Mayhem" campaign where the character "Mayhem" personifies everything that could go wrong in your life.

They present various potential very negative situations that resonate with you, positioning themselves as the solution to help you better cope with these challenges.

The message is clear: without the right insurance, you're vulnerable to all sorts of "mayhem" or disasters.

The ads play on the viewer's strong emotional response in the view of these potential disasters (negativity bias) and the potential losses they could incur (loss aversion).


Nike doesn't shy away from showcasing negative reviews alongside positive ones. Ok, now this sounds very counterintuitive.

Why would a platform want to highlight negative feedback?

Let me explain. Nike knows exactly we'll pay more attention to negative information. That's the whole point.

When users see both positive and negative reviews, they're more likely to trust the platform's authenticity. It feels genuine, balanced, and unbiased.

The presence of negative reviews can actually enhance the credibility of positive ones.

An example of the negativity bias with Nike negative reviews

In this case, negativity bias is not leveraged to drive immediate action but to build trust and credibility.

Tips Negativity bias.

  1. Highlight mistakes avoidance. Tell users how they can prevent problems or losses on your site. It'll grab attention as people are more inclined to avoid losses than make gains.
  2. Emphasize negative reviews. Got a product with mixed reviews? Show it! Users who see it might dig deeper to see if negatives are deal-breakers, increasing page engagement.
  3. Combine with Loss Aversion Bias. Accentuate possible losses and underscore negative outcomes to motivate users to take decisive action.

Peak–End Rule.

People remember and judge an experience by how they felt at its peak and at its end.


Definition Peak–End Rule.

The Peak-End Rule is a psychological bias whereby people judge an experience based primarily on what they felt at its peak and at its end, rather than on the sum total or average of each moment of the experience.

This effect occurs regardless of whether the experience is pleasant or unpleasant.

These peaks, when pleasant, often correspond to memorable experiences (cf. delighters) in the user's journey, hence the expression “ending on a good impression”, which refers to the “Peak-End Rule”.

Examples Peak–End Rule.


If the meal you had in a restaurant was horrible, and you ended it with a delicious dessert, you'll have better memories of it.


The break-up of a relationship is also a common example, as we can vividly recall a heartbreaking or painful break-up.


Tips Peak–End Rule.

  • Pay particular attention to the most intense points and final moments (the "end") of the user journey.
  • Identify the moments when your product is most useful, most valuable or most entertaining, and design it to delight the user at these moments.
  • Remember that people remember negative experiences more easily than positive ones.

Provide Exit Points.

Invite users to have a pleasant experience by offering them the possibility of opting out at the right moment.


Definition Provide Exit Points.

Create experiences that have a purpose. That way, users can walk away with a sense of accomplishment and satisfaction by allowing them to opt out.

Avoid creating an association between your product and wasted time. Exit points are designed to respect your users' time.

They are essential to a pleasant customer experience and to avoid product fatigue and reactance. (cf.: Peak-End Rule)

Examples Provide Exit Points.


TikTok is one place, filled with an endless stream of fun videos. However, this hugely popular video-sharing app can sometimes become a little too engaging, keeping you scrolling for hours on end.

Initially, TikTok invited users to quit the app after 2 hours by default.

Now, users can choose new time limits of 40, 60, 90 or 120 minutes, and decide how much time they want to spend on the app per day.

Exemple de Provide Exit Points dans l'application TikTok

Tips Provide Exit Points.

  • Simply respect your users' time by offering them value throughout their experience with your service. And when the time is right, invite them to stop on a positive note.

Sensory Appeal.

Users are more attracted by things that appeal to several senses.


Definition Sensory Appeal.

Why are we so drawn to the smell of bread in a bakery early in the morning?

When you walk into a bakery, the mere smell wafting from the oven is often enough to entice customers to buy pastries (simply by having enticed them in the first place).

The sights, sounds and smells that reach the street are rarely accidents. This is psychological marketing known as “sensory marketing”, designed to win your loyalty and, above all, attract you.

When several of these senses are engaged, people are more likely to form an emotional bond with the brand.

Examples Sensory Appeal.


In its stores, Apple offers shoppers a complete brand “experience”.

In these concept stores, customers are encouraged to see, touch and experience the entire Apple brand. The stores are designed to convince potential and current Apple buyers that this innovative brand is and will remain the key to benefiting from the latest innovations.


A pioneer in multisensory marketing, Starbucks' philosophy is to satisfy its customers' senses of taste, sight, touch and hearing.

The Starbucks brand offers this complete set of sensory satisfactions through the use of taste, aroma, and music (familiar depending on the country: familiarity bias). Thanks to this approach, consumers from all countries and cultures can share much more than just a good cup of coffee. They benefit from the whole “Starbucks experience”.


Let's take the example of the anime Demon Slayer and explain why it's such a global success?

This is partly due to its incredible animation quality, but many don't pay attention to its superb sound design and how it sublimates this piece of art.

"I've been a big anime fan since I was three apples tall, but I've never experienced such outstanding sound design for a work as I do with Demon Slayer." - Maxime Mroue

Tips Sensory Appeal.

  • Pay particular attention to the senses that your product or service conveys, relying more on these senses to sublimate your product.

Picture superiority effect.

People retain information much better when it's presented in images rather than words.


Definition Picture superiority effect.

Examples Picture superiority effect.


Tips Picture superiority effect.



People remember stories up to 22 times more than facts alone.


Definition Storytelling.

Examples Storytelling.


Tips Storytelling.



Gradually reinforce a target action to get closer to a given behavior.


Definition Shaping.

Examples Shaping.


Tips Shaping.



Users are more likely to remember the unexpected, playful pleasures of a product, which lends credence to the company.


Definition Delighters.

Examples Delighters.


Tips Delighters.

Availability heuristic.

Users prefer recent and available information to old.


Definition Availability heuristic.

Examples Availability heuristic.


Tips Availability heuristic.


Spacing effect.

Repetitions spaced out in time tend to produce stronger memories than repetitions closer together in time.


Definition Spacing effect.

Examples Spacing effect.


Tips Spacing effect.


Serial position effect.

People remember the first and last elements of a series better, and have trouble remembering those in the middle.


Definition Serial position effect.

Examples Serial position effect.


Tips Serial position effect.


Recognition Over Recall.

We're better at recognizing things we've already experienced than at remembering them.


Definition Recognition Over Recall.

Examples Recognition Over Recall.


Tips Recognition Over Recall.


Method of loci.

People remember things better when they are associated with a place.


Definition Method of loci.

Examples Method of loci.


Tips Method of loci.

Internal Trigger.

When users are asked to take action based on a memory.


Definition Internal Trigger.

Examples Internal Trigger.


Tips Internal Trigger.

💡 Psychology inspirations and resources.

If you'd like to learn more about behavioral psychology and mental models, we highly recommend taking a look at these resources:


Growth Design.

The idea and structure of this ressource is inspired by Growth Design.


The idea of creating a resource on cognitive bias was inspired by Growth Design.

Growth.design by Dan Benoni and Louis-Xavier Lavallee brings together a selection of Growth Design case studies and a cognitive bias resource like this one.

These case studies can help designers, product managers and marketers create memorable experiences for their customers.

Dan and Louis-Xavier do an amazing job, everything they share is a must-have for any marketer, it's one of the best marketing resources on the web!


Codex on cognitive bias.

The four categories on our list are taken from the work of Buster Benson.


Buster Benson did an impressive job of classifying cognitive biases. This has led him to create an enormous codex.

The four categories in this list are based on his research, so it's important that he be credited for his titanic work.

Buster Benson, author of the Codex on Cognitive Bias
Buster Benson

Author of "Why Are We Yelling?" - "We're all susceptible to cognitive biases, because our brains need them to think within the limits of the time and energy available to them. "


Super Thinking.

The big book on mental models and cognitive biases by Gabriel Weinberg.


Super Thinking deals with the methods and shortcuts that the best specialists in many disciplines use to free themselves from complexity and distinguish good ideas from bad ones.

Gabriel Weinberg on the importance of cognitive biasGabriel Weinberg on the importance of cognitive biasGabriel Weinberg on the importance of cognitive bias
Gabriel Weinberg

CEO of DuckDuckGo - "It's important to know the names of cognitive biases and mental models. Because once you have a name for something, you can start to spot it in the real world. And once you start spotting it, you can really start reaping the benefits."



How do you create habit-forming products from Nir Eyal?


This book immerses us in the psychology of habits and shows us: How do you create a product or service that anchors habits?

Nir Eyal is the author of the worldwide bestseller Hooked, and all his ideas are based on Eyal's years of research, consulting and hands-on experience.

PS: avoid the French version, catastrophic translation...


Influence and manipulation.

The psychology of persuasion by Robert Cialdini.



Contagious: why things go viral by Jonah Berger?


Predictably Irrational.

The hidden forces that shape our decisions by Dan Ariely.

📜 The Cognitive bias cheat sheet.

We've taken the time to summarize each bias in a short sentence.

These 109 cognitive biases can be found in our cognitive bias cheat sheet.

Use it to keep in mind your users' behavior towards your product.

Make sure they really appreciate your product, offer them a memorable experience!

<iframe src="https://assets-global.website-files.com/638234b816814da162a95761/63a0881b772ddaea2f41bddb_Antis%C3%A8che%20%20Psychologie%20du%20Design.pdf" name="biais" height="800px" width="100%"></iframe>
<a href="https://www.riseverse.com/ressources/biais-cognitifs" target="biais">La Psychologie du Design : liste de 106 Biais Cognitifs | RiseVerse</a>
Elon Musk on the importance of cognitive bias
Elon Musk

Tesla CEO - "Cognitive biases should be taught to everyone from an early age." - Tweet from Elon Musk (December 19, 2021)

👇 Now it's your turn to play.

So, which principle will you apply in your business?

Do you think we've forgotten to add an important cognitive bias or principles to this list?

If you have any questions at all, you can contact us at maxime@riseverse.com, we're happy to answer anyone, so don't hesitate!

See Our Work

Webflow Websites we’ve launched

Check a taste of our 50+ Webflow sites and the impact they've yielded to our clients - this is worth a thousand words about RiseVerse.

Ready to stand out and sell more?

Find out how we'll take your brand into a new era and get you to achieve your goals by setting up a discovery workshop with Greg, our co-founder.

Contact a Webflow Web Design Agency