How to use
- Tap the big box (or press the space bar) to start.
- Wait for it to turn green. If you tap while it is red, it counts as a false start.
- Tap the moment it turns green. Repeat five times.
- See your average and rating, then share it or try to beat your best.
What is a good reaction time?
Simple visual reaction time for most adults is about 200 to 300 ms. Under 200 ms is very fast. Results depend on your device too: screens and touch panels add roughly 10 to 50 ms of delay, so compare scores on the same device.
Frequently asked questions
Why is my score slower on my phone?
Touch screens and display refresh add delay. A desktop with a mouse and a high-refresh monitor usually gives the lowest numbers.
Can I improve my reaction time?
Sleep, caffeine and warming up help a little. Practice improves consistency more than raw speed.
Is my best score saved?
Yes, in this browser only.