Wait for green, then tap or click as fast as you can. Measure your average, best, and worst reaction times.
Test how quickly you can react. When the box turns green, tap or press Space as fast as possible. Your time is measured in milliseconds and shown alongside your average, best, and attempt count so you can track performance over a session.
This tool is useful for casual practice and curiosity, and it can also be a fun warm‑up before gaming sessions. It runs entirely in your browser, with results stored locally on your device. Multiple attempts help smooth out outliers, giving you a better sense of your typical reaction window.