Stopwatch

Measure elapsed time with laps. Pause does not count toward the total.

00:00:00.000

Uses performance.now() while running and corrects after the tab sleeps.

How it works

Running time is performance.now() minus the last resume instant, plus any previously accumulated spans. Lap rows show both split and total.

Questions

Does lap time include paused periods?

No. Only elapsed running time is accumulated.

Why milliseconds?

The stopwatch uses performance.now() while visible. After a hidden tab, elapsed time still comes from the high-resolution clock plus accumulated pauses.

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