Lights Out in the browser
Lights Out is a go-signal game. Five lamps light in sequence, then pause for a random beat, then all turn green. You tap, click, or press Space the instant they do. Go early and it is a false start. The number is your reaction time in milliseconds — a casual browser reading, not a medical or official racing test.
Controls
Watch the lamps. When they all turn green, tap the board, click, or press Space.
Scoring
Lower milliseconds is better. False starts do not count as a time. Best time stays on this device.
Want a longer walkthrough? How Lights Out Measures a Tap.