Reaction Speed Test

Test your reaction speed by clicking when the screen turns green

How to Use
Accurately measure your human reaction time to a visual stimulus. This reflex test calculates the exact milliseconds it takes for your brain to process the screen turning green and command your hand to click. **(100% browser-local processing, no server storage)**
1

Click 'Start Test' and keep your eyes focused on the red screen.

2

The moment the color shifts to green, click your mouse or tap the screen instantly.

3

Review your latency score in milliseconds. The system logs your attempts to find your true average.

Pro Tips

  • Do not anticipate the green screen. The delay is randomized to test true cognitive speed, not predictive timing.
  • For a scientifically reliable baseline, complete at least 5 consecutive trials to account for outliers.
  • After testing your visual reflexes, challenge your physical input speed with our [Typing Speed Test](/en/typing-speed-test).

Why Use This Tool?

Gain immediate, empirical data regarding your neurological readiness. This scientifically grounded reflex tool requires zero installation and provides unfiltered, ad-free latency testing directly within any modern web browser.

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