The asterisk, printed in full: your number includes hardware the browser cannot subtract — the display took 5–30 ms to actually show the teal, the mouse another 1–15 ms to report the click, and the OS batched events in between. A 240 ms reading on a 60 Hz office monitor and a 215 ms reading on a 240 Hz gaming panel can be the same nervous system. Compare runs on the same machine, and treat cross-device bragging accordingly.
What the milliseconds mean
- Under 200 ms — elite territory on typical hardware, and rare. Sprinters false-start under 100 ms because that's faster than humans react to sound.
- 200–250 ms — solidly quick. Most young, caffeinated gamers land here.
- 250–300 ms — the broad human average for a visual cue. Nothing wrong here.
- Over 350 ms — usually fatigue, distraction, or a laptop panel adding its own lag. Test again rested before concluding anything about your nervous system.
Visual reaction runs ~40 ms slower than auditory — light has to be processed by a slower pathway than sound. It's why starting pistols are pistols.
Getting a fair number
Sit as you normally sit; hover the finger; look at the center of the field, not the edges. Five rounds beats one — single readings swing ±50 ms on attention alone, which is why we don't score a single round. And skip the temptation to predict the rhythm: the pause is random precisely because your brain is excellent at learning rhythms and calling the result "reaction".