Reaction Time Test
Measure how fast you respond — a window into alertness and processing speed.
What it measures
Your simple reaction time — how many milliseconds pass between a signal appearing and your response to it. It reflects the speed of the whole loop: visual processing, decision, and motor output. Average reaction time is one of the most robust behavioural correlates of general processing speed and even of broader cognitive ability.
How it works
A panel asks you to wait, then turns green after an unpredictable 1.5–4 second delay. You click, tap, or press Space the instant it changes; we record the elapsed time with the browser’s high-resolution clock. Reacting before green counts as a false start and that trial is repeated. We take five valid trials and report your average and best time.
Tips for an accurate result
- 1Warm up first — Your first run is usually slower. A practice round or two settles you into a stable, honest baseline.
- 2Watch, don’t guess — Respond to the colour change itself. Pre-empting the signal inflates false starts and hides your true speed.
- 3Mind the basics — Sleep, caffeine, alcohol, and time of day all shift reaction time measurably — test under similar conditions to compare runs.
- 4Track the trend — A single number is noisy. Repeated measurements over days give a far more meaningful picture than one fast or slow run.