About Reaction Time Test

Reaction Time Test is a free online tool for measuring your reaction speed. Wait for the box to turn green, then click or press the spacebar as fast as you can — we measure the time between the green appearing and your response, in milliseconds.

Why

Most reaction tests just throw a number at you. We focus on context: every result comes with a grade and a percentile so you can see whether your reaction time is fast, and your best scores and recent history are kept right in your browser so you can track progress over time.

How it works

Timing runs entirely in your browser using a high-resolution clock. Each test runs several rounds and reports your average, median, best, and standard deviation, because a single click is never the whole story.

A note on accuracy

Your result reflects more than your reflexes — monitor refresh rate, mouse polling, and browser load all add a few milliseconds. This is a fun self-test, not a medical or scientific assessment.

Contact

Feedback or feature requests? Email hello@reactiontimetest.win.