How accurate is the online stopwatch?

It reads your device's high-resolution clock, so it is accurate to the hundredth of a second shown, and it does not drift.

Does it keep running in a background tab?

Yes. Time is calculated from the start time, so it is correct when you return to the tab.

Yes. Press Lap while it is running to record split and total times.

Online Stopwatch

A free online stopwatch with lap times, accurate to a hundredth of a second. Works in your browser, no download needed.

00:00:00.00

A simple online stopwatch

Start, stop and resume a stopwatch, and record lap times. Time is shown in hours, minutes, seconds and hundredths, and it keeps running accurately while you use other tabs.

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