Reaction Time Test

About Reaction Time Test

A reaction time test measures how quickly you respond to a visual cue, in milliseconds. Click to start, wait for the red screen to turn green, then click as fast as you can — clicking too early resets the round. Your average and best times are tracked so you can improve. It runs entirely in your browser, on desktop or mobile.

Frequently asked questions

What is a good reaction time?

The average visual reaction time is around 250 milliseconds. Under 200ms is excellent, and most people fall between 200 and 300ms.

What is the fastest possible reaction time?

Elite athletes react in roughly 150ms, and about 100ms is treated as the human limit — in sprinting, a start faster than 100ms after the gun is ruled a false start because no one can genuinely react that quickly.

How can I improve my reaction time?

With practice reflexes sharpen a little, but they're mostly biological. Being rested, focused, and using a low-latency mouse and monitor all help — repeat the test to track your average and best.

Does it work on a phone?

Yes. It runs in any mobile browser — tap to start, wait for green, then tap as fast as you can. Touch screens add a little input lag, so mobile scores tend to be slightly slower than a mouse.

Why did it say 'Too soon'?

You clicked while the screen was still red, before the green cue. The round resets so your score reflects a genuine reaction, not a guess.