How to play the Reaction Time test: rules, baseline, and how to improve
The Reaction Time test measures simple visual reaction time — the latency between seeing a stimulus and executing the corresponding motor response. It’s one of the oldest psychometric tests, and the measurement is genuinely interesting once you know what the numbers mean.
The rules in 30 seconds
The screen starts red. You wait. Eventually (after a random 1-5 second delay) it turns green. The moment you see green, you click as fast as you can.
The test measures how many milliseconds (ms) elapsed between the green appearing and your click landing. Five rounds; final result is your average across the five, plus your single best round.
If you click while the screen is still red, that round is invalidated and you start a fresh wait. No way to game it by predicting.
What counts as a 'good' reaction time
Adult human visual reaction time is bounded by physics and biology. Approximate ranges:
- 150-200 ms: very fast. Pro-gamer or young-and-rested elite. Most people will not see this number.
- 200-250 ms: fast. Trained athlete, pro driver, gaming enthusiast under ideal conditions.
- 250-300 ms: above-average. Most healthy adults under good conditions land here.
- 300-400 ms: average. The median adult’s reaction time on a monitor + mouse without warm-up.
- 400+ ms: below-average. Often a signal you’re tired, distracted, or running on a slow display.
There’s a hard floor around 100 ms — the latency of nerve impulses + muscle activation. Anyone reporting a result below 100 ms either has a measurement error or jumped the gun (clicked early on a prediction).
Things that legitimately move your number
- Sleep. The biggest factor. Sleep deprivation adds 50-100+ ms to your reaction time. Try the test after a good night vs. after a bad one — the difference is real.
- Caffeine.About 100-200mg lowers reaction time by 10-30 ms on average. More than that doesn’t help (and can hurt via shakiness).
- Display latency. A 60Hz monitor adds up to 16.7 ms of randomness per frame. A 144Hz or 240Hz monitor reports better numbers purely from lower display lag, not actual reflex improvement.
- Input device. Touchpads typically add 15-20 ms vs. a wired mouse. Touchscreen taps vary wildly by device.
- Posture and focus. Sitting upright, eyes locked on the screen, finger pre-positioned on the click target — these add up to 30-50 ms.
- Warm-up. Your first run of the day will be 20-40 ms slower than your fifth. The 5-round average mostly washes this out, but back-to- back runs will show the effect.
Things that DON'T move your number
- Trying really, really hard. Conscious effort can actually slow you down by adding deliberation overhead.
- Practicing the same test for hours. Reaction time has a hard physiological floor; you can’t train past it.
- Pre-clicking on prediction. Most reaction-time tests (including ours) detect early clicks and disqualify the round. Patience is faster than guessing.