All 138 Cognitive Biases
Browse the complete catalogue of cognitive biases, organised by how they shape thinking. Each bias includes a definition, real-world examples, warning signs, countermeasures, and an interactive thought experiment.
Social & Perception29 biases
07Halo Effect10Bandwagon Effect16Projection Bias18Actor-Observer Bias20Confirmation Cascade21Fundamental Attribution Error24False Consensus Effect28Spotlight Effect37In-Group Favoritism39Naive Realism40Illusion of Transparency41Out-Group Homogeneity Effect42Cheerleader Effect43Bystander Effect44Groupthink45Social Loafing46System Justification47Identifiable Victim Effect48Hostile Attribution Bias49Moral Credential Effect50Ben Franklin Effect51Naive Cynicism52Shared Information Bias53Trait Ascription Bias54Out-Group Derogation55Third-Person Effect56Compassion Fade57Illusion of Asymmetric Insight58Proximity Bias
Memory & Attention28 biases
03Availability Heuristic08Negativity Bias11Framing Effect17Hindsight Bias29Zeigarnik Effect32Mere Exposure Effect35Google Effect36Survivorship Bias59Baader-Meinhof Phenomenon60Peak-End Rule61Von Restorff Effect62Cryptomnesia63Serial Position Effect64Misinformation Effect65Spacing Effect66Testing Effect67Levels of Processing Effect68Context-Dependent Memory69Generation Effect70Next-in-Line Effect71Fading Affect Bias72Duration Neglect73Source Confusion74Picture Superiority Effect75Telescoping Effect76Pollyanna Principle77Sleeper Effect78Attentional Bias
Decision & Choice27 biases
02Anchoring06Sunk Cost Fallacy09Status Quo Bias19Decoy Effect22Gambler's Fallacy33Planning Fallacy34Unit Bias79Hyperbolic Discounting80Choice Overload81Zero-Risk Bias82Default Effect83Omission Bias84Action Bias85Ambiguity Aversion86Certainty Effect87Disposition Effect88Mental Accounting89Money Illusion90Distinction Bias91Less-is-Better Effect92Regret Aversion93Escalation of Commitment94Pseudo-Certainty Effect95Pro-Innovation Bias96Information Bias97Automation Bias98Well-Traveled Road Effect
Belief & Confidence27 biases
01Confirmation Bias04Dunning-Kruger Effect14Overconfidence Effect15Optimism Bias23Curse of Knowledge25Backfire Effect26Barnum Effect99Base Rate Fallacy100Authority Bias101Illusory Truth Effect102Semmelweis Reflex103Belief Bias104Hot-Hand Fallacy105Clustering Illusion106Subadditivity Effect107Neglect of Probability108Normalcy Bias109Catastrophizing110Illusion of Explanatory Depth111Illusion of Validity112Congruence Bias113Continued Influence Effect114Rhyme-as-Reason Effect115Law of Small Numbers116Disconfirmation Bias117Moral Luck Bias118Just-World Hypothesis
Outcome & Self27 biases
05Loss Aversion12Self-Serving Bias13Regression to the Mean27IKEA Effect30Endowment Effect31Ostrich Effect38Declinism119Illusion of Control120Self-Consistency Bias121Impact Bias122Focalism123Restraint Bias124Hard-Easy Effect125Worse-Than-Average Effect126Better-Than-Average Effect127Choice-Supportive Bias128Egocentric Bias129Subliminal Priming Effect130Outcome Bias131Stereotyping132Ego Depletion Bias133Anthropomorphism Bias134Bias Blind Spot135Decline Effect136Illusion of Agency137Neglect of Prior Probability138Self-Fulfilling Prophecy