Stopwatch Online
Millisecond precision stopwatch with lap timer. Start, stop, record laps, and reset — all in your browser.
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Lap Times
How to Use
- Click Start to begin timing.
- Click Lap to record a lap time while the timer keeps running.
- Click Stop (same button as Start) to pause the timer.
- Click Reset to clear the timer and all laps back to zero.
What Is It?
A stopwatch is a timer that measures elapsed time from a start point. Millisecond-precision stopwatches are used in athletics, cooking, laboratory experiments, music practice, and coding performance testing. Our browser-based stopwatch uses performance.now() for accurate millisecond timing that is unaffected by clock adjustments.
Why Use Our Tool?
- ✓Millisecond precision using performance.now() — not Date.now().
- ✓Unlimited lap recording with individual lap and total times displayed.
- ✓Copy all lap times to clipboard in one click.
- ✓Works entirely in the browser — no download or app needed.
Frequently Asked Questions
- The stopwatch uses performance.now() for millisecond precision — far more accurate than Date.now(). Display updates every 50ms.
- There is no limit. All laps are recorded and displayed below the timer.
- Yes. After recording laps, click Copy Lap Times to copy all laps to the clipboard.
- The display pauses if the browser tab is hidden, but the timer continues running accurately and resumes when you return to the tab.
- Yes, completely free.