Curiosity Lab

Cognitive Bias Explorer

Thinking shortcuts have names, but the names are easier to use than the evidence is to summarize. Each entry gives a plain definition, an example, and what is contested or unknown about it.

Anchoring: A tendency for an initial number or reference point, even an arbitrary one, to pull later estimates toward it.
Availability heuristic: Judging how common or likely something is by how easily examples come to mind.
Bandwagon effect: A tendency to adopt beliefs or behaviours because many others have, as popularity itself becomes a signal.
Base-rate neglect: Ignoring how common something is overall when judging a specific case, and focusing on case details instead.
Confirmation bias: A tendency to search for, notice and remember information that fits what we already believe, and to scrutinise information that does not.
Dunning-Kruger effect: The pattern that people with low skill in an area tend to overestimate their performance there, while high performers tend to slightly underestimate theirs.
Endowment effect: Valuing something more simply because we own it, so that selling prices exceed buying prices.
Framing effect: Choices shift depending on how identical information is worded, such as survival rates versus mortality rates.
Fundamental attribution error: Explaining other people's behaviour by their character while underrating the situation they are in.
Hindsight bias: After learning an outcome, feeling that it was obvious or predictable all along.
Illusory truth effect: Statements feel more true after repeated exposure, regardless of whether they are true.
Loss aversion: Losses tend to feel stronger than gains of the same size.
Negativity bias: Bad events, feedback and information tend to weigh more heavily than equally strong good ones.
Optimism bias: Expecting good outcomes to happen to oneself more than to others, and bad ones less.
Planning fallacy: Underestimating the time, cost and risk of a project even when similar past projects ran over.
Spotlight effect: Overestimating how much other people notice our appearance or mistakes.
Status quo bias: A preference for the current state of affairs, so that change must clear a higher bar than staying put.
Sunk cost fallacy: Continuing with something because of what has already been spent, rather than what it will cost or return from here on.
Survivorship bias: Drawing conclusions from the cases that survived a selection process while ignoring those that did not.

How to use this list

A named bias is a description of a pattern, not an explanation of any one decision, and not an accusation. Some patterns have replicated well; others have weaker or mixed support. Each card shows an evidence note so you can tell which is which.

Cognitive Bias Explorer

The tool

How to use this list