What your Stroop score means
Your result is the extra time you needed when the word and its color clashed, in milliseconds and as a percentage of your speed on matching words. A smaller gap means you were better at ignoring the word. Accuracy matters too: if you missed more than 30% of the colors, the timing isn’t meaningful, so it isn’t scored.
| Slowdown on clashing words | Rating |
|---|---|
| Under 8% | Strong focus control |
| 8–20% | Typical |
| 20–35% | Noticeable interference |
| Over 35% | Strong interference |
These bands are a rough guide for this version of the task, not published norms.
The Stroop effect, explained
In 1935, psychologist J. Ridley Stroop asked people to name the ink colors of 100 color words printed in clashing colors. It took them 74% longer than naming the colors of plain squares, an extra 47 seconds. Reading the same words aloud while ignoring their color was barely affected, slowing people by only about 6%.
That asymmetry is the whole point: for a fluent reader, reading is automatic and color naming is not. The test shows how hard your attention has to work to block a habit, and it has become one of the most studied tasks in psychology.
What the Stroop test measures
It measures selective attention and inhibitory control, two of the brain’s executive functions: picking out what matters and holding back an automatic response. Psychologists use versions of it to study attention, aging and practice, alongside many other measures.
How to get a better Stroop score
- Soften your focus and look at the color of the letters’ edges rather than the word’s shape.
- Say the color in your head (“red”) before you move.
- Keep a steady rhythm. Rushing raises mistakes more than it saves time.
- Play rested. The effect grows when you are tired.
Stroop test FAQ
What does a big Stroop effect mean?
Only that reading took over more than usual on this attempt. Tiredness, rushing and a new device all widen the gap, so it says more about how you were doing today than about who you are.
Can I take the Stroop test if I’m colorblind?
You can play, but red and green are hard to tell apart for many colorblind people, so your score won’t be comparable. The interference comes from color names, so the test can’t avoid colors.
Is the Stroop test an IQ test?
No. It measures one executive skill: overriding an automatic habit (reading) to follow a rule (naming the color). IQ tests measure reasoning across several areas.
Why is reading so hard to switch off?
For fluent readers, reading a word happens automatically, before you decide to do it. Naming a color takes a deliberate step, so when the two clash, the automatic answer gets in first.
Sources
- Stroop, J. R. (1935). Studies of interference in serial verbal reactions. Journal of Experimental Psychology, 18(6), 643–662.
- MacLeod, C. M. (1991). Half a century of research on the Stroop effect: An integrative review. Psychological Bulletin, 109(2), 163–203.
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Take the free IQ testBy the MyIQTest team · Reviewed November 2026