About Reaction Time Test

What This Tool Measures

This test measures your visual reaction time — the total time from when a visual stimulus appears on screen to when your hand completes a click or tap. It captures the full chain: light hitting your retina, your brain processing the signal, and your motor system executing the response. This is not a measure of pure neural reflex speed; it includes perception, decision-making, and motor output all in one number.

How We Built It

Timing Accuracy

We use the browser's performance.now() API to record timestamps, which provides sub-millisecond precision (typically < 1 ms). The stimulus start time is captured immediately when the screen turns green, and the response time is recorded the instant your click or tap event fires — giving you the most accurate measurement possible in a browser environment.

Device Latency Disclaimer

Your score is affected by hardware outside our control. A monitor with a 60 Hz refresh rate introduces up to ~16.7 ms of display latency; a 144 Hz display reduces that to ~7 ms. Input device latency (wired vs. wireless mouse, touchscreen digitizer) adds another 5–20 ms. These offsets are consistent across your sessions on the same device, so your scores are comparable within a device — but cross-device comparisons should account for these hardware differences.

Who This Is For

  • Curious individuals who want a quick, fun baseline measurement of their own reflexes.
  • Gamers and esports players looking for a repeatable benchmark to track improvement from training.
  • Students and researchers needing a simple, accessible introduction to reaction time concepts before diving into more rigorous laboratory tools.

Data & Privacy

We do not collect or store any personal data. Your test scores are saved only in your browser's localStorage, which means they stay on your device and are never transmitted to our servers. For full details, see our Privacy Policy.

Contact Us

Have a question, found a bug, or want to share feedback? Email us at contact@reactiontest.app and we'll be happy to help.