Reaction Time Test
How fast are your reflexes? Click the moment the box turns green and see your reaction time in milliseconds. Everything runs locally in your browser.
New to this? Read the Reaction Time guide →
- Last reaction
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- Average (last 5)
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- Best
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Click the box to begin.
Average human reaction time to a visual cue is around 200–300 ms. The keyboard works too — focus the box and tap Space. Nothing is uploaded.
How the reaction test works
- Click to start, then wait. The screen is red.
- The moment it turns green, click as fast as you can.
- Your time in milliseconds appears, along with your average and best. Click too early and it tells you to wait for green.
The wait before green is randomised so you cannot anticipate it, which is what makes the test measure genuine reaction rather than timing.
What's a good reaction time?
For a simple visual cue like this, the average adult lands around 200 to 250 milliseconds. Under 200 ms is fast, and consistently near 150 ms is excellent. There is a hard floor: signals take time to travel from your eyes to your brain to your hand, so nobody reacts in single-digit milliseconds. A handful of runs gives a fairer picture than a single attempt.
What affects your score
- Sleep, caffeine, alertness and fatigue all move the number.
- Input lag from your display, mouse and connection adds a few milliseconds.
- Warming up with a few practice rounds usually helps.
Want to compare with a friend? Share your best as a "beat it" link, or save a result image.
Frequently asked questions
What is a good reaction time?
The average human reaction time to a visual cue is around 200-300 ms. Under 200 ms is excellent, and competitive gamers and athletes often score in the 150-200 ms range.
Why does my reaction time vary so much?
Reaction time is affected by focus, fatigue, screen and input lag, and even how you anticipate the cue. Taking several attempts and using the average is more reliable than a single result.
Is my reaction time saved or uploaded?
No. The test runs entirely in your browser and your results stay in the current tab.
Where you'd use this
Getting an honest baseline for reflexes, and seeing what genuinely changes it — sleep, caffeine, the display you are using — rather than what people claim changes it.
For example: You score 240ms on a desktop monitor and 290ms on a laptop. That 50ms is mostly display latency, not you — which is worth knowing before blaming your aim for losing duels.