For self-help and reflection. Not medical advice. Not a substitute for therapy.

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Cognitive Distortion Detector

Type a thought you've been having. We'll show you which thinking patterns might be amplifying it — and a calmer way to look at it.

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Get all 12 distortions as a printable reference card.

6-page PDF. Names each pattern, gives a calmer reframe for each. Print and keep on your desk. No email needed.

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Reference

The 12 cognitive distortions, in plain language.

These are the 12 patterns the detector looks for. Each one is a normal mental shortcut that becomes painful when it runs unchecked. Reading them doesn't fix anything by itself — but seeing the pattern is what creates space to choose differently.

#01

All-or-Nothing Thinking

black-and-white thinking, polarized thinking, dichotomous thinking

You see things in absolute, black-or-white categories. There's no middle ground — something is either perfect or a total failure, you're either successful or worthless.

"If I don't get this promotion, my career is over."

ReframeLook for the middle ground. What does "good enough" look like here? Most outcomes live on a spectrum, not at the extremes.

#02

Catastrophizing

magnifying, awfulizing, worst-case thinking

You expect the worst possible outcome and assume you couldn't cope with it. A small problem balloons into an imagined disaster.

"My boss didn't reply to my email — I'm going to be fired."

ReframeAsk: what's the most likely outcome, not the worst? And: even if the bad thing happened — could I get through it?

#03

Mind-Reading

assuming, projecting

You assume you know what other people are thinking — usually something negative about you — without any actual evidence.

"She didn't smile back. She must think I'm annoying."

ReframeWhat evidence do I actually have? What are 3 other reasons their behaviour could be explained — none of which involve me at all?

#04

Fortune-Telling

predicting the future, anticipating disaster

You predict the future negatively, treating an imagined outcome as if it's already a fact. Different from catastrophizing — here you don't necessarily go worst-case, you just feel certain you know what will happen.

"There's no point applying — I won't get the job anyway."

ReframeNotice the certainty. You don't actually know. What if you replaced "I will" with "I might" — does the thought still feel as heavy?

#05

Should Statements

musts, oughts, have-tos

You criticize yourself or others with rigid "shoulds", "musts", and "have-tos". The result is guilt when applied to yourself, anger when applied to others.

"I should have known better. I shouldn't be this upset over nothing."

ReframeTry replacing "should" with "would prefer" or "could". "I would prefer to have handled that better." Same intent, no shame layer.

#06

Labeling

global labeling, name-calling

Instead of describing a behaviour, you assign a global, identity-defining label — to yourself or someone else. "I made a mistake" becomes "I'm a failure."

"I forgot to reply to her message. I'm such an awful friend."

ReframeSwitch from identity to behaviour: "I did X" instead of "I am X". One action does not equal a whole identity.

#07

Personalization

self-blame, taking it personally

You blame yourself for events that aren't fully (or at all) your responsibility. You take personal hits for outcomes shaped by many people, contexts, and accidents.

"My friend was quiet at dinner. It must be because of something I said."

ReframeDraw a responsibility pie chart. How much is genuinely yours? What % belongs to context, other people, biology, randomness?

#08

Emotional Reasoning

feelings as facts

You take an emotion as proof of a fact. "I feel like a failure" becomes evidence that you are one. "I feel anxious" becomes evidence something bad will happen.

"I feel guilty, so I must have done something wrong."

ReframeFeelings are signals, not verdicts. Try: "I feel X — and that's just a feeling. The feeling doesn't prove anything about reality."

#09

Mental Filter

negative filtering, tunnel vision

You pick out a single negative detail and dwell on it exclusively, while filtering out everything that went well. Your brain treats the one criticism as the headline.

"My presentation got 9 great responses and 1 critical one. I can't stop thinking about the critical one."

ReframeForce the full picture. Write down 3 things that went well alongside the one negative thing. Look at the ratio.

#10

Disqualifying the Positive

doesn't count, just lucky

Positive things happen but you find a reason they don't count. "They were just being polite." "That was luck." "It doesn't really mean anything."

"They said the project was great, but they probably just say that to everyone."

ReframeTry the test: would you discount this if a colleague told you the same story? If no, you're applying a special rule only to yourself.

#11

Overgeneralization

always-and-never thinking, broad-brushing

You take a single negative event and conclude it will happen forever, in every situation. One rejection becomes "I'll always be alone."

"I bombed that interview. I'll never get hired anywhere."

ReframeCatch the "always" / "never". Replace with "this time" or "in this situation". One data point isn't a trend.

#12

Fairness Fallacy

it's not fair, comparing fairness

You measure life by your own definition of fairness — and feel resentful or miserable when reality doesn't comply. Life rarely operates by anyone's personal fairness rule.

"It's not fair. I worked harder than her and she got the promotion."

ReframeTrade "fair" for "useful". What does this situation actually require of me right now, regardless of fairness?

Method & sources

The 12-pattern list is the standard set used in cognitive behavioural therapy, originating in Cognitive Therapy and the Emotional Disorders (Beck, 1976) and popularised in Feeling Good: The New Mood Therapy (Burns, 1980). Detection is rule-based pattern matching — it surfaces likely candidates but cannot diagnose. For clinical use, please consult a licensed therapist.

Questions

Common questions about cognitive distortions

What is a cognitive distortion? +
A cognitive distortion is a habitual pattern of thinking that bends reality in a misleading way. They feel true in the moment but don't hold up to evidence. Identifying them is the first step in cognitive behavioural therapy (CBT) — once you see the pattern, the thought loses some of its grip.
Is this tool a substitute for therapy? +
No. This is an educational reference for self-reflection. It does not provide diagnosis, treatment, or medical advice. If you're experiencing distress, please contact a licensed therapist. In Germany, Telefonseelsorge offers free 24/7 support at 0800 111 0 111.
Where does the data go when I type a thought? +
Nowhere. Detection runs entirely in your browser using rule-based pattern matching. Nothing is sent to a server, logged, or stored. Close the tab and the input is gone.
Why are my matches not perfect? +
The detector uses keyword and phrase patterns — it can't understand nuance the way a therapist can. Use the matches as starting points for reflection, not as final answers. The most useful question is: 'Does this label fit, even partly?'
Why does the same thought match multiple distortions? +
Because they often co-occur. A thought like 'I'll never get this right and everyone thinks I'm useless' contains overgeneralization ("never"), mind-reading ("everyone thinks"), and labeling ("useless"). Recognising the layers helps you address each one.
How was the list of 12 distortions chosen? +
It's based on Aaron Beck's foundational CBT work (1976) and David Burns's Feeling Good (1980), which together established the standard list used in CBT practice today. We've kept the original 12 and adapted the language for self-reflection rather than clinical use.
What do I do after I identify the distortion? +
Use the suggested reframe template as a starting point. Better: write the thought down, pick the strongest matching distortion, and complete a thought record (situation → thought → distortion → balanced view). We have a free PDF that walks you through it.
Are these distortions a sign of something serious? +
No. Every human has cognitive distortions — they are normal mental shortcuts. They become a problem only when they're frequent, intense, and tied to suffering. If that resonates, please speak with a licensed therapist.
Can I use this tool anonymously? +
Yes. No login, no email, no cookies for analytics. Your input never leaves your browser.
Where can I learn more? +
Our free Cognitive Distortions Quick Guide covers all 12 patterns with extended examples and reframes. We also recommend David Burns's book Feeling Good as the canonical introduction.

Go deeper

If you want the full guide that backs this tool, plus our other free tools — same calm-design system, your data stays in the browser:

The 12 Cognitive Distortions: A Plain-Language Guide

Cornerstone reference: every distortion in detail, with mechanism, examples, and reframe templates. 13 min read.

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Burnout Stage Identifier

16-question self-check across exhaustion, cynicism, and efficacy.

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If a thought feels overwhelming

This tool is for self-reflection. It is not therapy and not medical advice. If a thought is causing severe distress, persistent low mood, or thoughts of self-harm, please contact a licensed therapist. Free 24/7 support is available — in Germany via Telefonseelsorge at 0800 111 0 111, in the EU via 112, in the US via 988.