How to play Reaction Test
- Click the panel (or press Space) to start a round. It turns red: wait.
- After a random delay of 1.5 to 5 seconds it turns green. Click or press Space as fast as you can.
- Clicking before green counts as too early and the round restarts, so don't try to guess the timing.
- After five rounds you get your average. Run it again whenever you like.
Scoring
- Each round measures the milliseconds between the panel turning green and your click, using the browser's high-resolution timer.
- The average of five rounds is your result. Only the best average is saved.
Tips
- Use a mouse or keyboard rather than a touchpad; touchpads add a few milliseconds of their own.
- Rest a finger on the button or key. Movement distance is part of the measurement.
- Focus on the colour, not the timing. Trying to predict green produces early clicks.
- Warm up with one run; the first attempt is usually the slowest.
What is a typical reaction time?
Most adults score between 200 and 300 milliseconds on a simple visual reaction test like this one. Around 250 ms is common; well under 200 ms is fast and often seen in gamers and athletes. Reaction time to sound is slightly quicker than to light, and it slows gradually with age, fatigue and distraction.
Your monitor and input device add delay that is outside your control. A 60 Hz display can add up to 16 ms before the green frame appears, and wireless peripherals add a few more, so compare results on the same setup.
Scores and preferences for this game are stored only in your browser's local storage. Nothing is sent to a server and no account is needed. Browse all games.