Stroop test
A colour word will appear in coloured ink. Click the button for the INK colour and ignore what the word says. Be fast, but accurate.A colour word will appear in coloured ink. Tap the button for the INK colour and ignore what the word says. Be fast, but accurate.
About 1 minute · 40 words · Saved only if you choose
Private by design: your answers never leave this page.
This test relies on telling colours apart, so it may not work well for people with colour-vision differences.
Skip to the attention span test →Practice round
A colour word will appear in coloured ink. Click the button for the INK colour and ignore what the word says. Be fast, but accurate.A colour word will appear in coloured ink. Tap the button for the INK colour and ignore what the word says. Be fast, but accurate.
Practice complete
Ready for the real test? 40 words in random order. Be fast, but accurate.
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What does it mean?
What can change it?
Reading speed, practice, tiredness and how fast you try to go.
These bands are our own guide to help you read your result. They're not compared with a population, and they're not a diagnosis.
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What’s happening in this test?
Practise first. Four practice words with feedback come first. They don't count.
Name the ink. Each word is a colour name printed in a colour. Pick the ink colour, not the word, with the buttons or the R, B, G and Y keys.
Forty words. Half the words match their ink and half clash. You have 3 seconds for each word, and no answer counts as a miss.
The gap. Your Stroop effect is your average time on clashing words minus your average time on matching words, using correct answers only.
What can change your result: reading speed, practice, tiredness and how fast you try to go. Colour-vision differences can affect it too.
Read more: The Stroop effect, explained
Questions
What is the Stroop effect?
Naming the ink colour takes longer when the word names a different colour. Reading is so automatic that it gets in the way.
Who discovered it?
J. Ridley Stroop, in experiments published in 1935.
What does the Stroop test measure?
How well you can focus on one thing (the ink) while ignoring a strong habit (reading the word).
Is a bigger Stroop effect bad?
Not really. It mostly shows how automatic your reading is. It's a fun look at how your attention works, not a grade.
Is this a medical test?
No. It's for curiosity and self-reflection.
Learn more: The Stroop effect, explained
Sources
- Stroop, J. R. (1935). Studies of interference in serial verbal reactions. Journal of Experimental Psychology.
- MacLeod, C. M. (1991). Half a century of research on the Stroop effect. Psychological Bulletin.