Reaction Time Test
Human reaction time to a visual signal typically falls between 200 and 300 milliseconds. This test measures yours precisely, using nothing but your click and your browser's high-precision timer.
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Best: —
Attempts: 0
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About This Game
The screen will turn from red to green at a random moment. Click as soon as you see green — but not before, or you'll have to start again. Your best time is saved on this device so you can track improvement over multiple attempts.
Frequently Asked Questions
What's considered a good reaction time?
Most healthy adults score between 200-300 milliseconds on simple visual reaction tests. Elite athletes and gamers sometimes reach the 150-180ms range with practice, though genetics play a real role too.
Does reaction time change with age or tiredness?
Yes — reaction time naturally slows with fatigue, and gradually with age, particularly after the mid-20s. Caffeine, sleep quality and even the device you're using can all measurably affect your score.
Why did my click sometimes not register a time?
If you click before the screen turns green, the test resets to prevent guessing rather than genuinely reacting to the signal — this keeps your measured score honest.