How the reaction time test works
Click the blue box to begin. It turns red, and after a random pause of 1.5 to 5 seconds it turns green. Click or tap the moment you see green. The time between the colour change and your click is your reaction time, measured in milliseconds with the browser's high-resolution timer. If you click while it is still red, the try does not count. After 5 (or 10) valid tries you get your average, median, fastest and slowest result.
What is a normal reaction time?
For a simple visual task like this, results between about 200 and 300 ms are commonly reported for healthy adults, and many people land near the middle of that range. Your number also includes the delay of your screen, mouse or touch screen and browser, which can add several tens of milliseconds, so compare scores on the same device. The median is the fairest single number because one slow try does not drag it up.
What affects your reflexes?
- Sleep and fatigue – tiredness is one of the biggest causes of slow and uneven results.
- Attention – looking at the box and not your phone makes a real difference.
- Device – a wired mouse and a high refresh-rate screen usually give lower times than a phone touch screen.
- Practice – results often improve a little over the first few rounds as you get used to the test.
Tips for a better score
Rest your finger lightly on the mouse button, relax your hand, and keep your eyes on the centre of the box. Do not try to guess the moment; the pause is random, and early clicks only cost you time. Play a couple of warm-up rounds, then do the 10-try test for a stable average. This tool is for fun and practice, not a medical or professional assessment.
FAQ
Is this reaction time test free?
Yes. It is free, works in any browser and needs no account. Results stay in your own browser.
Why are my results different on my phone?
Touch screens and phone displays add their own delay. Compare results on the same device only.
What counts as a good reaction time?
For this kind of test, roughly 200–300 ms is commonly seen in adults; lower is faster. Treat it as a rough guide.
What does the median mean?
It is the middle result when all tries are sorted, so a single slow or lucky try changes it less than the average.
Can I use the keyboard?
Yes. Press Space or Enter instead of clicking.