Wait for the screen to turn green, then click as fast as you can. Five measurements — at the end you get your average, your best time and where that sits among the reference ranges.
Reference ranges for simple visual reaction — the kind of stimulus this test uses. They are there to place you, not to assess you clinically.
| Range | Reading | Who usually lands there |
|---|---|---|
| < 180 ms | Exceptional | Trained players, wired mouse, high refresh rate monitor |
| 180–219 ms | Fast | Frequent players, or anyone practised at the gesture |
| 220–269 ms | Average | Most adults, on any device |
| 270–329 ms | Below average | Fatigue, divided attention, slower phone |
| ≥ 330 ms | Slow today | Poor sleep, distraction, or a first attempt |
A single measurement says very little: 40 ms of spread between rounds is normal. That is why this test averages five, and why the comparison that matters is you against yourself, on the same device.
Time zero is captured inside the frame that paints the green — not when the code asks for the colour. A whole frame can pass in between, and that gap is how looser tests hand out times better than reality.
The end comes from the timestamp the browser puts on the input event when it is created. If the page stalls for 30 ms before the code runs, that delay does not land on your score.
No browser test can separate you from your device: the panel has to light up and the touch has to be read. A phone adds tens of milliseconds over a wired mouse. Always compare on the same hardware.
In LapseGP the job is not just being fast: it is stopping the chronometer on the target time, to four decimals, with a margin that shrinks every level. Free, in your browser, one lap per ten seconds.
The gap between a stimulus appearing and your body responding. Here the stimulus is the screen turning green and the response is your click. The number covers your eye and brain registering the change, your hand moving — and your device's own latency.
For simple visual reaction, most adults land between 200 and 300 ms, averaging near 250 ms. Under 200 ms is fast. Under 180 ms shows up mostly among people who play a lot and use a wired mouse on a high refresh rate monitor.
It does. The touchscreen and the panel add frames to the path. That does not mean you got slower — it means the device joined the measurement. To track your own progress, compare runs made on the same hardware.
Within limits. Sleep, attention and practice at the specific gesture help; fatigue, alcohol and distraction do the opposite. Much of what feels like “getting faster” is anticipation — learning the rhythm of the stimulus. With a randomised wait like this one, anticipating too hard just becomes a jump start.
Because one is noise. Normal same-day variation runs to a few tens of milliseconds, so the average of five describes your current state far better than any single click — including your best one.