Reaction Time Test

Measure how fast you react when the screen turns green.

Runs entirely in your browser - nothing is sent to a server.

Related tools

How it works

1
Click Start

Wait for the red box to turn green.
2
Click as fast as you can

Your reaction time in milliseconds appears instantly.

FAQ

What happens if I click too early?: It counts as a false start - click Start again to retry.
What is a good reaction time?: Under 200ms is excellent, 200-300ms is good, 300-450ms is average for most people.