About this reaction time test
A reaction time test measures how quickly you respond to a visual signal. The pad turns red while you wait, then green after a random delay of 1.5 to 4 seconds — the randomness stops you from guessing the rhythm. The moment it turns green, click (or tap) as fast as you can. After 5 rounds the tool shows your average reaction time in milliseconds, your best single round, and saves your personal best on your device. Gamers use it to warm up, and it's a fun way to compare reflexes with friends — or to see what a cup of coffee actually does.
Frequently asked questions
- What is a good reaction time?
- The median human reaction time to a visual signal is around 250 milliseconds. Under 200 ms is very fast, 200–250 ms is quick, and most people land between 250 and 320 ms. Age, fatigue, caffeine and your display all shift the number.
- Why does the test use 5 rounds?
- A single click is noisy — you might guess or get lucky. Averaging 5 rounds smooths out the luck and gives a much more repeatable measure of your true reaction speed.
- Why is my reaction time worse than the numbers I see quoted?
- Your measured time includes your monitor's refresh and input lag, your mouse latency, and the browser's event handling — usually 20–60 ms of overhead on top of your biological reaction. Compare scores on the same device rather than across devices.
- What happens if I click too early?
- Clicking while the pad is still red doesn't count and doesn't ruin your run — the round simply restarts. Only clicks after the pad turns green are measured.