Reaction Time Test
Wait for the screen to turn bright, then click, tap or press Space as fast as you can. Two practice presses, then five timed ones. You get your median in whole milliseconds, every trial shown, and a plain account of what your screen and mouse add. Nothing is subtracted and nothing is uploaded.
2 practice · 5 timed · about a minute
About this reaction time test
How to use it
- Click the test area, tap it, or press Space. Two practice presses come first; you can skip them.
- Keep still while the screen says "Wait for it…". The wait is random, between 1.5 and 4.5 seconds, and mostly unpredictable.
- When the screen turns bright and says GO, press as fast as you can. Use whichever you like: mouse, touch or keyboard. Results are kept per input.
- After five timed presses you get your median. Run it again, or run the 20-trial version for a steadier number.
What the number means
- Observed reaction time is the median of your timed presses, in whole milliseconds. The median is used because one distracted slow press should not wreck the result, and one lucky guess should not flatter it.
- Too soon: a press before GO, or under 100 ms after it, is faster than a visual reaction can be. It is counted, shown, and the trial is repeated.
- Slow: 500 ms or more still counts. Slow reactions are real reactions.
- Missed: no press within a second. Counted, shown, and repeated.
- Repeated: if the tab lost focus or your browser skipped a frame at the moment GO appeared, that attempt did not measure a reaction, so it is repeated and the reason is shown.
Why is my reaction time worse on a 60 Hz monitor, a laptop or a phone?
The screen can only change at its next frame, your mouse or touchscreen takes time to report a press, and the computer and browser add their own delay. None of that is you. It is also why the same person gets different numbers on different computers and on different websites. Compare your runs on the same setup; the page keeps that history on your device.
Am I faster with the spacebar than with the mouse?
Often, a little, because keyboards and mice reach the computer differently. This page records which input you used and keeps the histories separate, so you can see the difference for yourself.
Is a sub-150 ms score real?
Rarely for a visual signal. Lab averages sit around 230 ms on calibrated equipment, and a browser adds delay on top. Very fast scores usually come from anticipating the signal, which this test counts as a false start below 100 ms and reports honestly above it. Look at the spread and the false-start count, not just the median.
How do I compare?
Human Benchmark reports a median of 273 ms across its visitors on their own devices. A calibrated lab study of 1,469 adults found 231 ms, including 17.8 ms of measured equipment delay (Woods et al. 2015). Neither is a percentile for you: the equipment differs, and so does this page's timing method. We do not show "faster than X% of people", because no honest reference population exists for browser tests.
Method
The wait before GO is 1.5 s plus a random exponential part averaging 1 s, capped at 4.5 s, so the signal stays mostly unpredictable. GO is a single-frame brightness change with an icon and text, never a colour difference alone. The timer starts when the page applies GO inside a frame callback and stops at the press event's own timestamp. Trials are repeated when the tab is hidden, the window loses focus, the GO frame is drawn late, or the input type changes. Version 1.0.0.
Privacy
Everything runs in your browser. Nothing is uploaded and there is no account. Your results are kept only on this device, grouped by setup, and you can clear them. Saved files are created on your device and only go where you send them.