Reaction Time Test
Wait for the screen to turn from red to green, then react right away: click, tap, or press the Space bar. After 5 tries, you'll know your average reaction time in milliseconds.
- Time in milliseconds
- Series of 5 tries
- Average and best time
- Click, tap, or Space
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How to test your reaction time?
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Wait for green
The screen stays red for a random delay, so no one can guess the right moment. Clicking before then shows “too early”.
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React
As soon as the screen turns green, click, tap the screen, or press Space: your time is shown in milliseconds.
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Finish the series
Go through all 5 tries to get your average and your best time, which are more reliable than a single try.
Your reflexes measured in milliseconds
Random delay
Green appears at an unpredictable moment: you measure your reaction, not your ability to anticipate.
False starts detected
A click before green is flagged “too early”: no way to get a flattering time by clicking at random.
Average over 5 tries
Your average and your best time, much more representative than a single lucky try.
Click, tap, or Space
Mouse, touchscreen, or Space bar: take the test on a computer, a phone, or a tablet.
What's the average reaction time?
Faced with a visual signal like this switch to green, an adult reacts in about 250 milliseconds on average, or a quarter of a second. Around 250 ms, you're average; between 200 and 250 ms is a good result, and under 200 ms an excellent one. Professional esports players often land around 150 to 200 ms. Below 100 ms, it's almost always anticipation rather than reaction: in track and field, a sprinter who leaves the blocks less than 100 ms after the starting gun is called for a false start.
Screen, mouse, fatigue: what affects your result
The time displayed doesn't only measure your reflexes: it also includes your hardware's delay. A 60 Hz screen only displays a new image every 16.7 ms, a mouse adds a few milliseconds, and a touchscreen often a bit more; a gaming monitor at 144 Hz or higher narrows the gap. On the human side, fatigue and distractions noticeably slow your reflexes, as does alcohol, even in small amounts. Lack of sleep takes a heavy toll: after 17 to 19 hours without sleep, performance is as impaired as with a blood alcohol level of 0.5 g/L (0.05%), the legal driving limit in many countries.
Reaction time behind the wheel and in video games
In a shooter or a fighting game, a few dozen milliseconds often make the difference: measuring your reflexes lets you track your progress or compare two mice or two monitors. Behind the wheel, reaction is much slower than in this test, because you have to spot the danger, decide, then hit the brake: count on about one second, or roughly 80 feet (25 meters) traveled at 55 mph before you even start braking. This same delay limits the accuracy of any timing done by hand, including with our “Online Stopwatch”. To measure your clicking speed rather than your reflexes, try the “Click Speed Test (CPS)”.
Frequently Asked Questions
What's a good reaction time?
Around 250 ms, you're average. Under 200 ms is an excellent result; professional esports players often land around 150 to 200 ms.
Why does my time vary from one try to the next?
Attention fluctuates from moment to moment and the delay before green changes with each try: a few dozen milliseconds of difference is normal. That's why the test calculates an average over 5 tries.
What does “too early” mean?
You clicked before the screen turned green. The delay is random precisely to prevent anticipation: really wait for the color change before reacting.
Am I faster on a computer or on a phone?
Often on a computer, with a mouse and a high-refresh-rate monitor: a touchscreen or a 60 Hz screen adds a few milliseconds. To track your progress, retake the test on the same device.
Can you improve your reaction time?
A little: getting enough sleep, staying focused, warming up, and practicing regularly all help. Fatigue, alcohol, and some medications slow it down significantly.