How precise is the stopwatch?

Timing is measured with Date.now() deltas, which gives millisecond accuracy. The display updates at your screen refresh rate (typically 60 frames per second) and shows milliseconds directly.

Will the stopwatch drift if I leave the tab running in the background?

No. Elapsed time is calculated from the start timestamp plus any accumulated offset, not by counting ticks, so browser background-tab throttling has no effect on accuracy.

Can I keep my laps when I pause and resume?

Yes. Pause and resume preserve all recorded laps. Laps are only cleared when you press Reset.

Stopwatch

Precise stopwatch with millisecond accuracy and lap tracking.

00:00:00.000

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