DeviTestReaction time test
Wait for the box to turn green, then click as fast as you can. Your average over 5 rounds is your reaction time.
What's a normal reaction time?
Most people react to a visual signal in about 250 milliseconds. Under 200 ms is excellent, and trained gamers often reach 150–180 ms. Tiredness, distractions and caffeine all change the result, so take the average of several tries.
Your screen and mouse matter too
Part of the time you measure is your equipment: the screen's refresh rate, its input lag and the mouse's response all add a few milliseconds. A 144 Hz monitor can shave around 10 ms off compared with 60 Hz. Check yours with the refresh rate test.
You can also press Space to play. This test isn't a medical assessment — it's just for fun and practice.