Reaction Time Test — How Fast Are Your Reflexes?
Measure your visual reaction time over five tries with false-start detection and a personal best. Free, no sign-up, and your files never leave your device.
Free, with no sign-up and no watermark. The file is processed in your browser and never uploaded.
Click (or press Space) the moment the box turns green. Five tries give an average, median, fastest and slowest time, and your personal best is remembered on this device. Clicking before green is caught as a false start and not scored.
Step by step
- Start: Click the box or press Space. It turns red — wait.
- React: When it turns green, click or press Space as fast as you can.
- Repeat: Click again for the next try. After five tries you get a full summary.
- Compare: Check your Average, Median and Personal best in the results.
Handy for
Gaming
Benchmark your reflexes and track improvement.
Alertness check
Slower times can show fatigue.
Classroom experiments
Compare groups, times of day or caffeine — fairly, on one device.
Good to know
Use the same device each time: screens and mice add their own 10–50 ms delay.
Keyboard Space is often slightly faster than a mouse click.
Turn off battery saver; low frame rates delay when the green appears.
Questions
What is a good reaction time?
Most people average 200–300 ms on visual tests like this. Under 200 ms is exceptionally fast.
How is the time measured?
From the frame where the box is painted green to the timestamp of your click or key press, using the browser’s high-resolution clock.
Is anything sent to a server?
No. The test runs entirely in your browser and nothing is uploaded or stored online.
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