Reaction Time Test
Click on the green cue and measure your reaction time, with a multi-trial average.
Written by Golam Rabbani, Founder & Lead Engineer
How to use this reaction time test
- Click the panel (or press Space) to start a trial.
- Wait for the panel to turn green — do not click while it is red.
- Click as fast as you can the moment it turns green; your time in milliseconds appears immediately.
- Repeat for several trials to build a stable average; the result panel shows your best and average.
- Press Reset to clear all trials and start over.
About this reaction time test
This reaction time test measures the gap, in milliseconds, between a visual cue (the panel turning green) and your click or keypress. It uses the browser's high-resolution timer, so the figure you see reflects real wall-clock latency rather than the slower 16ms-resolution of legacy timers.
Each trial introduces a random delay of between 1.2 and 4 seconds before the green cue. Clicking before the cue triggers a "too soon" state so anticipation does not pollute your score. After at least three trials, the panel reports both your best single trial and the rolling average across all trials, which is a much fairer benchmark than any one round.
For example, you run five trials and get 248 ms, 221 ms, 267 ms, 235 ms, and 218 ms. The best is 218 ms and the average is (248 + 221 + 267 + 235 + 218) / 5 = 237.8 ms — comfortably inside the typical 200–300 ms human range for simple visual reactions. Most of the latency you measure is brain processing time; the keyboard or mouse adds only a few milliseconds on a modern setup.
FAQ
- What counts as a good reaction time?
- For a simple visual stimulus, the average healthy adult lands around 250 ms. Anything below 200 ms is fast, and elite athletes and gamers regularly score 150–180 ms.
- Why does the screen sometimes flash yellow?
- You clicked before the panel turned green. That trial is discarded so anticipation does not inflate your score; just click the yellow panel to try again.
- Does my monitor refresh rate affect the result?
- A little. A 60Hz display adds up to ~16ms of jitter compared to a 240Hz display, but the variance between trials in your own reactions is much larger than that.
- How many trials should I run for an accurate score?
- Five to ten trials is plenty. The average stabilises quickly once you stop having outlier rounds where you blinked or got distracted.
- Can I use a keyboard instead of clicking?
- Yes. Tab to the panel and press Space or Enter to start a trial, then press it again on green. The timing is identical to mouse input.
- Is my data saved?
- No. The trials live only in memory and are wiped when you reload or close the page.