๐Ÿง  Psychology of Design106 Cognitive Biases & Principles That Affect Your UX

Every time users interact with your product, they:

  1. ๐Ÿ™ˆ Filter the information
  2. ๐Ÿ”ฎ Seek the meaning of it
  3. โฐ Act within a given time
  4. ๐Ÿ’พ Store bits of the interaction in their memories

So to improve your user experience, you need to understand the biases & heuristics affecting those four decision-cycle steps.

Below is a list of cognitive biases and design principles (with examples and tips) for each category. Letโ€™s dive right in.

PS: Donโ€™t have time to read the whole list?ย Get the cheat sheet

๐Ÿ™ˆ Information

Users filter out a lot of the information that they receive, even when it could be important.

๐Ÿ‘€ Hick's Law

More options leads to harder decisions

Expand โ†“

๐Ÿ’ผ Confirmation Bias

People look for evidence that confirms what they think

Expand โ†“

๐Ÿ‘ Priming

Previous stimuli influence users' decision

Expand โ†“

๐Ÿš› Cognitive Load

Total amount of mental effort that is required to complete a task

Expand โ†“

โš“๏ธ Anchoring Bias

Users rely heavily on the first piece of information they see

Expand โ†“

๐Ÿ‘‰ Nudge

Subtle hints can affect users' decisions

Expand โ†“

๐Ÿฐ Progressive Disclosure

Users are less overwhelmed if they're exposed to complex features later

Expand โ†“

๐ŸŽฏ Fitts's Law

Large and close elements are easier to interact with

Expand โ†“

๐Ÿ•บ Decoy Effect

Create a new option that's easy to discard

Expand โ†“

๐Ÿ–ผ Framing

The way information is presented affects how users make decisions

Expand โ†“

๐Ÿ  Attentional Bias

Users' thoughts filter what they pay attention to

Coming Soon

๐Ÿ’” Empathy Gap

People underestimate how much emotions influence user behaviors

Coming Soon

โ›ต๏ธ Visual Anchors

Elements used to guide users' eyes

Coming Soon

๐ŸŒถ Von Restorff Effect

People notice items that stand out more

Coming Soon

๐ŸŽ– Visual Hierarchy

The order in which people perceive what they see

Coming Soon

๐Ÿ”ญ Selective Attention

People filter out things from their environment when in focus

Coming Soon

โœˆ๏ธ Survivorship Bias

People neglect things that don't make it past a selection process

Coming Soon

๐Ÿ’ Juxtaposition

Elements that are close and similar are perceived as a single unit

Coming Soon

๐Ÿšฆ Signifiers

Elements that communicate what they will do

Coming Soon

๐ŸŽญ Contrast

Users' attention is drawn to higher visual weights

Coming Soon

๐Ÿšจ External Trigger

When the information on what to do next is within the prompt itself

Coming Soon

๐ŸŽช Centre-Stage Effect

People tend to choose the middle option in a set of items

Coming Soon

๐Ÿฃ Law of Proximity

Elements close to each other are usually considered related

Coming Soon

๐Ÿฌ Tesler's Law

If you simplify too much, you'll transfer some complexity to the users

Coming Soon

๐Ÿงจ Spark Effect

Users are more likely to take action when the effort is small

Coming Soon

๐Ÿฅ Feedback Loop

When users take action, feedback communicates what happened

Coming Soon

๐Ÿ˜ป Expectations Bias

People tend to be influenced by their own expectations

Coming Soon

๐Ÿš† Aesthetic-Usability Effect

People perceive designs with great aesthetics as easier to use

Coming Soon

๐Ÿ”ฎ Meaning

When users try to give sense to information, they make stories and assumptions to fill the gaps.

๐Ÿ‘ฅ Social Proof

Users adapt their behaviors based on what others do

Expand โ†“

๐Ÿฆ„ Scarcity

People value things more when they're in limited supply

Expand โ†“

๐Ÿ’ญ Curiosity Gap

Users have a desire to seek out missing information

Expand โ†“

๐Ÿ–ฒ Mental Model

Users have a preconceived opinion of how things work

Expand โ†“

๐Ÿ‘จโ€๐Ÿ‘ฉโ€๐Ÿ‘งโ€๐Ÿ‘ฆ Familiarity Bias

People prefer familiar experiences

Expand โ†“

๐Ÿ•น Skeuomorphism

Users adapt more easily to things that look like real-world objects

Expand โ†“

๐ŸŽ Reciprocity

People feel the need to reciprocate when they receive something

Expand โ†“

๐Ÿค Singularity Effect

Users care disproportionately about an individual as compared to a group

Expand โ†“

๐ŸŽฐ Variable Reward

People especially enjoy unexpected rewards

Expand โ†“

๐ŸŽ‰ Aha! moment

When new users first realize the value of your product

Expand โ†“

๐Ÿฅ… Goal Gradient Effect

Motivation increases as users get closer to their goal

Expand โ†“

๐Ÿ’ˆ Occamโ€™s Razor

Simple solutions are often better than the more complex ones

Expand โ†“

๐ŸŽ— Noble Edge Effect

Users tend to prefer socially responsible companies

Expand โ†“

๐Ÿงฟ Hawthorne Effect

Users change their behavior when they know they are being observed

Expand โ†“

๐Ÿ‘ผ Halo Effect

People judge things (or people) based on their feelings towards one trait

Coming Soon

โ˜Ž๏ธ Millerโ€™s Law

Users can only keep 7ยฑ2 items in their working memory

Coming Soon

๐Ÿฑ Unit Bias

One unit of something feels like the optimal amount

Coming Soon

๐ŸŒŠ Flow State

Being fully immersed and focused on a task

Coming Soon

๐Ÿ‘‘ Authority Bias

Users attribute more importance to the opinion of an authority figure

Coming Soon

๐Ÿบ Pseudo-Set Framing

Tasks that are part of a group are more tempting to complete

Coming Soon

๐ŸŽŠ Group Attractiveness Effect

Individual items seem more attractive when presented in a group

Coming Soon

๐Ÿšฐ Curse of Knowledge

Not realizing that people don't have the same level of knowledge

Coming Soon

๐Ÿ“ฎ Self-Initiated Triggers

Users are more likely to interact with prompts they setup for themselves

Coming Soon

โœ๏ธ Survey Bias

Users tend to skew survey answers towards what's socially acceptable

Coming Soon

๐ŸŽญ Cognitive Dissonance

It's painful to hold two opposing ideas in our mind

Coming Soon

๐Ÿ’ซ Feedforward

When users know what to expect before they take action

Coming Soon

๐Ÿ’ Hindsight Bias

People overestimate their ability to predict outcomes after the fact

Coming Soon

๐ŸŽ Law of Similarity

Users perceive a relationship between elements that look similar

Coming Soon

๐ŸŒ“ Law of Prรคgnanz

Users interpret ambiguous images in a simpler and more complete form

Coming Soon

๐Ÿ˜ Streisand Effect

When trying to censor information ends up increasing awareness of that information

Coming Soon

๐Ÿ”ฆ Spotlight Effect

People tend to believe they are being noticed more than they really are

Coming Soon

๐Ÿ—“ Fresh Start Effect

Users are more likely to take action if there's a feeling of new beginnings

Coming Soon

โฐ Time

Users are busy so they look for shortcuts and jump to conclusions quickly.

๐Ÿง—โ€โ™‚๏ธ Labor Illusion

People value things more when they see the work behind them

Expand โ†“

๐Ÿšถโ€โ™‚๏ธ Default Bias

Users tend not to change an established behavior

Expand โ†“

๐Ÿฆ Investment Loops

When users invest themselves, they're more likely to come back

Expand โ†“

๐Ÿ•ฏ Loss Aversion

People prefer to avoid losses more than earning equivalent gains

Expand โ†“

๐Ÿ‘ž Commitment & Consistency

Users tend to be consistent with their previous actions

Expand โ†“

๐Ÿ Sunk Cost Effect

Users are reluctant to pull out of something they're invested in.

Expand โ†“

๐ŸŒ‹ Reactance

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

Expand โ†“

๐Ÿ”จ Law of the Instrument

If all you have is a hammer, everything looks like a nail

Expand โ†“

๐Ÿญ Temptation Bundling

Hard tasks are less scary when coupled with something users desire

Expand โ†“

๐ŸŽฉ Dunning-Kruger Effect

People tend to overestimate their skills when they don't know much

Expand โ†“

๐Ÿ” Discoverability

The ease with which users can discover your features

Expand โ†“

๐Ÿ Second-Order Effect

The consequences of the consequences of actions

Expand โ†“

๐ŸŒ› Decision Fatigue

Making a lot of decisions lowers users' ability to make rational ones

Coming Soon

๐Ÿฅฝ Observer-Expectancy Effect

When researchers' biases influence the participants of an experiment

Coming Soon

๐ŸŒฑ Weber's Law

Users adapt better to small incremental changes

Coming Soon

๐ŸŽˆ Parkinsonโ€™s Law

The time required to complete a task will take as much time as allowed

Coming Soon

๐ŸŒค Affect Heuristic

People's current emotions cloud and influence their judgment

Coming Soon

๐Ÿ“‰ Hyperbolic Discounting

People tend to prioritize immediate benefits over bigger future gains

Coming Soon

โŒš๏ธ Chronoception

People's perception of time is subjective

Coming Soon

๐Ÿ’ณ Cashless Effect

People spend more when they can't actually see the money

Coming Soon

๐ŸŒš Self-serving bias

People take credits for positive events and blame others if negative

Coming Soon

๐Ÿฅฌ Pareto Principle

Roughly 80% of the effects come from 20% of the causes

Coming Soon

๐Ÿ”ซ Backfire Effect

When people's convictions are challenged, their beliefs get stronger

Coming Soon

๐ŸŒˆ False Consensus Effect

People overestimate how much other people agree with them

Coming Soon

๐Ÿš‹ Bandwagon Effect

Users tend to adopt beliefs in proportion of others who have already done so

Coming Soon

๐Ÿง™โ€โ™‚๏ธ Barnum-Forer Effect

When you believe generic personality descriptions apply specifically to you.

Coming Soon

๐Ÿ›‹ IKEA Effect

When user partially create something, they value it way more

Coming Soon

๐Ÿงšโ€โ™‚๏ธ Planning Fallacy

People tend to underestimate how much time a task will take

Coming Soon

๐Ÿ’พ Memory

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

๐Ÿ• Provide Exit Points

Invite users to leave your app at the right moment

Expand โ†“

๐ŸŽข Peak-End Rule

People judge an experience by its peak and how it ends.

Expand โ†“

๐Ÿ‘… Sensory Appeal

Users engage more with things appealing to multiple senses

Expand โ†“

๐Ÿงฉ Zeigarnik Effect

People remember incomplete tasks better than completed ones

Expand โ†“

๐Ÿงค Endowment Effect

Users value something more if they feel it's theirs

Expand โ†“

๐Ÿ› Chunking

People remember grouped information better

Expand โ†“

๐Ÿ’š Delighters

People remember more unexpected and playful pleasures

Expand โ†“

๐Ÿ’› Internal Trigger

When users are prompted to take action based on a memory

Expand โ†“

๐Ÿ“ธ Picture Superiority Effect

People remember pictures better than words

Coming Soon

๐Ÿ“Œ Method of Loci

People remember things more when they're associated with a location

Coming Soon

๐Ÿงญ Shaping

Incrementally reinforcing actions to get closer to a target behavior

Coming Soon

๐Ÿ’พ Recognition Over Recall

It's easier to recognize things than recall them from memory

Coming Soon

๐Ÿฐ Storytelling Effect

People remember stories better than facts alone

Coming Soon

๐Ÿ‘น Negativity Bias

Users recall negative events more than positive ones

Coming Soon

โฐ Availability Heuristic

Users favor recent and available information over past information

Coming Soon

๐ŸŒŒ Spacing Effect

People learn more effectively when study sessions are spaced out

Coming Soon

๐Ÿ Serial Position Effect

It's easier for users to recall the first and last items of a list

Coming Soon

Product Psychology Resources

If you want to learn more about behavioral psychology and mental models, we recommend these resources:

๐Ÿ““ Cognitive Biases Codex

The four categories of our list come from Buster Benson's work

Expand โ†“

๐Ÿ“˜ Super Thinking

The big book of mental models and cognitive biases (Gabriel Weinberg)

Expand โ†“

๐Ÿ“™ Hooked

How to build habit-forming products (Nir Eyal)

Expand โ†“

๐Ÿ“• Influence

The psychology of persuasion (Robert Cialdini)

Coming Soon

๐Ÿ“” Predictably Irrational

The hidden forces that shape our decisions (Dan Ariely)

Coming Soon

Cognitive Biases Cheat sheet

We took the time to summarize each principle in one line.

They are all in a free cheat sheet of cognitive biases principles.

You canย download this cheatsheet as a PDF here.

Use it as a user empathy reminder while you build a feature.

Nir Eyal
โ€œWe all have a responsibility to build ethically-designed products and services to improve peopleโ€™s lives. Growth.Designโ€™s list of cognitive biases and psychological principles is a great reference for any team committed to improving their customersโ€™ user experience. Dan & Louis-Xavierโ€™s comic book case studies show you how.โ€โ€” Nir Eyal, bestselling author of Hooked and Indistractable

Now Itโ€™s Your Turn

So which principle are you going to try next?

Are there missing elements we should add to the list?

You can reach us at team@growth.design, we reply to everyone!

Mission

We believe that sharing meaningful experiences makes the world better. GrowthยทDesign helps organizations across the world craft better products and experiences.

About

All rights reserved
ยฉ 2023 GrowthยทDesign inc.
All Bitmoji Avatars are owned
by Snap Group Limited. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Grown in Montreal ๐Ÿ‡จ๐Ÿ‡ฆ