Stroop Test — Name the Ink Color, Not the Word
A color word appears, printed in ink of a different color. Tap the color you see — not the word you read.
- Twenty trials. Half are easy (the word matches its ink), half are not.
- Answer as fast as you can, but a wrong answer is not counted in your time.
- At the end you get your interference gap: how much slower the mismatched trials made you.
0 / 20
—
TAP THE INK COLOR
YOUR INTERFERENCE GAP
0ms
How much slower the mismatched trials made you
- Word matched ink
- 0 ms
- Word fought ink
- 0 ms
- Accuracy
- 0%
This is a game, not a medical or cognitive screening tool. It cannot detect or rule out any condition, and a large gap is normal — the Stroop effect is something almost everyone shows. If you are worried about attention or memory, speak to a doctor rather than a web page.
About the Stroop Test
The Stroop Test shows you a color word printed in the wrong color — the word RED written in blue ink — and asks you to name the ink, not the word. Reading is so automatic that the word answers before you do, and pushing that answer aside costs time you can measure. This page runs twenty trials, half matched and half mismatched, and reports the difference between them in milliseconds. That difference is the point: absolute speed varies with your device, your age and how much coffee you have had, but the gap between your own two conditions is a comparison inside yourself. John Ridley Stroop published the effect in 1935 and it has been reproduced ever since, which is why it turns up in psychology courses and brain-training apps alike. Ours is built from scratch with five colors — we do not use items from any commercial Stroop instrument. It is a game. It does not diagnose anything, and almost everyone shows the effect.
Stroop (1935), "Studies of Interference in Serial Verbal Reactions" — full text
How the Stroop Test works
- Press Start. A color word appears in the middle of the screen.
- Tap the button matching the color of the ink. Ignore what the word says — that is the whole difficulty.
- Half the trials are congruent (the word RED really is red) and half are incongruent. They alternate, so neither half can dominate your score.
- Answer quickly but honestly. Wrong answers are left out of the timing averages, so guessing fast will not flatter your result.
- After twenty trials you get three numbers: your congruent average, your incongruent average, and the gap between them.
- Play again on the same device to compare. Comparing across devices mostly measures the devices.
Stroop Test FAQ
Is the Stroop Test free, and do I need to sign up or install anything?
It is free with no account, no email and no install. Everything runs in the page you are already looking at, and no result is sent anywhere or stored.
How long does the Stroop Test take?
About forty seconds. Twenty trials, each one a single tap, with a short pause between them so your answer registers cleanly.
Can this tell me if I have ADHD or dementia?
No, and please do not use it that way. The Stroop task appears inside some clinical assessments, but a clinical assessment is a trained person using a standardized instrument alongside your history — not twenty taps on a website. This page reports a number and deliberately gives no verdict. If you are worried about your attention or memory, that is a conversation for a doctor.
What counts as a normal gap?
We do not publish a normal range, on purpose. Published figures come from controlled labs with calibrated equipment, and your gap here also contains your phone's touch latency and how you were holding it. Compare your own runs on the same device instead — that comparison is meaningful and a comparison to a stranger's number is not.
Why did I score worse than last time?
Fatigue, distraction, a different hand, a different browser, or just variance across only twenty trials. Reaction-time measures are noisy at this length. If you want a steadier picture, run it three times and look at the middle result rather than the best one.
What makes this different from other Stroop pages?
Most report raw speed, which is dominated by your device rather than by you. This one separates matched and mismatched trials and reports the difference, which is the part the Stroop effect actually describes. It also excludes wrong answers from the averages, so a fast guesser does not out-score a careful reader.
Does color blindness affect the result?
It can. The task assumes you can tell the five ink colors apart, so if red and green look similar to you the mismatched trials get harder for a reason that has nothing to do with attention. Every answer button shows the color name next to its swatch, which helps, but the stimulus word itself is color only.
Is there a minimum age? Can children take it?
There is no age limit and no account, but this one has a real floor: the task only works if reading is already automatic for you. The whole effect comes from the printed word answering before you can stop it, so a child who is still sounding words out may show a smaller gap than an adult — not because their attention is better, but because the word is not yet interfering. Read a young child’s result as a game rather than a measure. And as above, we do not publish a normal range at any age, so there is nothing here to rank a child against.