A free reaction time test for your phone or computer. Wait for the screen to turn green, then tap as fast as you can. Ten rounds, with your two fastest and two slowest dropped, give you a fair average in milliseconds and a percentile against other players.
Average visual reaction time is roughly 250 milliseconds. Under 200 ms is fast; under 150 ms is exceptional.
Yes, slightly. Screen refresh rate and touch latency can add a few milliseconds, so compare scores on the same device.
Yes. No signup, no download and no app. It runs in your phone or computer browser.