About us
A timer, not a verdict
Reaction Test is a small, independent tool for measuring visual reaction time. No account, no adverts, no leaderboard to climb — just a clean measurement you can repeat, keep and share if you want to.
What the test measures
It measures simple visual reaction time: the gap between a green signal appearing and your finger responding. That gap contains three things — your eye and brain registering the change, your muscles carrying out the movement, and the delay added by your screen, browser and input device.
Most healthy adults land between 200 and 300 milliseconds. Athletes and gamers often sit lower. A blink takes roughly 100 to 150 milliseconds, which is why nobody honestly scores 50.
How we time it
The clock starts on the frame where the panel is painted green and stops on your first pointer or key event, using the browser's high-resolution timer. The wait before the signal is randomised between 1.2 and 3.5 seconds so it cannot be anticipated. Tapping early voids the attempt and restarts it rather than quietly inflating your average.
Three attempts per round is deliberate. One attempt is noise; three give you a best and an average without the fatigue that makes long runs unreliable.
Reading your number honestly
Touchscreens usually report 20 to 60 milliseconds slower than a wired mouse, and a high-refresh monitor flatters you against a 60 Hz laptop panel. Compare yourself against your own history on the same device, and treat cross-device comparisons as rough.
This is a curiosity and a training toy. It is not a medical or diagnostic instrument, and a slow result is not a finding about your health.
Who made it
Reaction Test is run by a two-person team who got tired of reaction tests buried under pop-ups. The site stays deliberately small: one page of test, four pages of plain writing, and your records kept on your own device rather than ours.
Corrections and ideas are welcome on the contact page. New to the test? Start with how to play.