Click the moment the screen changes — your average reflex speed in milliseconds
Reaction Time is the classic green-screen test: wait, and click the instant the colour changes. Because the delay is randomised you cannot anticipate it, and clicking early invalidates the round. It gives you a number in milliseconds that is stable enough to track over weeks.
Click to begin and wait on the holding screen.
The screen turns green after a random delay.
Click the instant it changes.
Clicking before the change is a false start.
Several rounds are averaged into your result.
A test is five rounds. After you tap, the screen waits a random 1.5 to 5 seconds before turning green, so the change cannot be predicted. Tap too early and that round simply restarts; early taps are counted but never scored.
Your result is the average of the five times, in milliseconds. Each time is rated: under 150 ms 'superhuman', under 200 'pro gamer', under 250 'above average', under 300 'average'. Your best average is saved in this browser.
Simple visual reaction time. It is one of the few cognitive measures with an unambiguous unit, and one of the most sensitive to sleep, alertness and age. Another reaction game to try next: Simple Click Reaction. Every game in this family is on the reaction games page. Our reaction time test guide explains what counts as a fast or slow score. Speed of thinking, not just of the finger, is the subject of processing speed training.
Measuring reaction time is where experimental psychology began: in 1868 F. C. Donders used differences in response times to estimate how long mental steps take. A single stimulus with one response — this test — gives simple reaction time, the fastest kind; adding choices slows people predictably, a relationship known as Hick's law.
Typical simple reaction times for young adults are around 200 to 250 milliseconds on a screen, and they slow with age. In a large Scottish cohort study, faster and more consistent reaction times were associated with higher cognitive ability. Your device adds its own delay, so compare your scores on the same device.
Hover, do not rest. A finger in contact with the button will press before you decide to.
Watch the centre of the screen. Peripheral detection adds a few milliseconds.
Do not count the delay. The randomisation exists to make anticipation useless.
Average at least five clean rounds. Single results swing far too much to mean anything.
Figures around 200-250 ms for visual reaction are widely quoted, but measured values vary with hardware by enough to make cross-site comparison meaningless. Compare against your own history.
A 60 Hz display can add up to 16 ms of frame latency alone, plus input lag and processing. A phone and a gaming monitor will give the same person very different numbers.
It does, gradually and consistently, in every large study that has looked. Practice and alertness both shift it back somewhat.
Same measure, different presentation. Quick Tap uses fifteen rounds of a moving target; this is the classic single-screen version.