Wait for the signal, then click or press Space as quickly as you can.
Measure one clean reaction. No account or score upload.
Best --Average human reaction time is roughly 200 to 250 ms.
Rules
- Start a round and wait for the panel to turn green.
- Click as soon as the green signal appears.
- Clicking during the waiting phase counts as a false start.
- Your score is the elapsed time between the signal and your click. Lower is better.
The first click after a completed round starts another round. The best result is kept for this tab only.
A brief history
Reaction-time tests became common in psychology and human-factors research during the nineteenth and twentieth centuries. Simple visual-response tests are still used to study attention, decision speed, and hand-eye coordination. This browser version keeps the experiment short and playful.
Privacy
The signal delay, reaction time, and best score are calculated locally. No account or network request is required.