Reaction Time Test: Millis

How fast are you, actually?

Reaction Time measures the gap between seeing something change and moving your finger — and it measures it correctly.

Most reaction apps stop the clock when your finger lifts off the glass. That adds your own release time to every single result, which is why their numbers run slow. This one stops the moment your finger lands.

FOUR WAYS TO MEASURE

• Simple — the screen turns green, you tap. Raw reaction, nothing else. • Choice — one of four panels lights up. Tap that one. • Go / No-Go — green means tap, red means hold still. Speed plus restraint. • Timing — a bar sweeps toward a line. Tap exactly when it arrives.

STATISTICS, NOT JUST A HIGH SCORE

Five valid attempts per session. You get the median (the number worth trusting), your best, your mean, and your spread — how consistent you were. Attempts under 100 ms are marked as false starts and attempts over 3 seconds as misses. Both are shown to you and both are left out of the maths, with the reason on screen.

WHAT IT DOES NOT DO

• No account. Nothing to sign up for. • No paywall and no subscription. Every test is free. • No data collected. Your sessions never leave this iPhone. • Works completely offline, including in airplane mode.

Tiers are our own scale, not a population percentile. This app is for measurement and entertainment, not medical or cognitive assessment.