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Reaction Time
Wait for green, then tap. Beat your personal best.
Brain 10 sec
A blank screen turns green at a random moment. Tap the instant it does.
When to use this
- Quick energy check: See if your brain is awake or still booting up.
- Before a hard task: A 10-second wake-up jolt before you dive into deep work.
- Best of three with a friend: Instant micro-tournament, no setup required.
- Track your reflexes over time: Your personal best lives in this browser — beat it.
Tap to start
A green flash is coming. React as fast as you can.