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Reaction Time Test

What is this tool?

A reaction time test that runs entirely in your browser with millisecond precision. It times the gap between the trigger and your response using performance.now() and low-latency pointerdown/keydown events, so it measures your reflexes rather than browser lag. Three modes let you test visual reaction (react to green), auditory reaction (react to a beep) and choice reaction (pick the correct box, which adds cognitive processing time). Clicking before the signal is caught as a false start and doesn't count.

When to use it

  • Checking your reflexes before a competitive gaming session
  • Comparing your visual, auditory and decision-making reaction speeds
  • Tracking whether sleep, caffeine or fatigue change your reaction time
  • Challenging friends to beat your average on the same mode
  • Just seeing how you stack up against the average human benchmark

How to use it

  1. 1Pick a mode — Visual, Audio or Choice
  2. 2Click Start and wait for the trigger (don't click too early)
  3. 3React as fast as you can with a click, tap, or the Space/Enter key
  4. 4Repeat for five attempts — false starts simply repeat the attempt
  5. 5Read your average, tier and percentile, then download the result card or copy your score

Frequently asked questions

How is the reaction time measured?

It uses the browser's high-resolution performance.now() clock and low-latency pointer/key events, timing from the moment the trigger appears (captured at paint) to your response — so it reflects your reflexes, not rendering delay.

What is a good reaction time?

Most people land around 250–300 ms on a visual test. Under 200 ms is elite gamer or athlete territory, and under 150 ms is exceptional. The tool grades every attempt against these benchmarks.

What happens if I click too early?

A click before the signal is flagged as a false start. That attempt doesn't count toward your average — you just repeat it, so guessing never helps your score.

How is the percentile calculated?

It's an estimate from the well-known distribution of human simple reaction time (mean ~273 ms). It's a model for context, not a live global leaderboard.

Are my scores saved or uploaded?

Your personal bests and history are stored only in this browser, and the test runs entirely on your device — nothing is sent to a server.