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Stopwatch.

A precise browser stopwatch with lap recording. Start, stop, record laps, and reset — no app needed.

00:00:00.0

    A simple, precise stopwatch that runs in your browser. Tap Start to begin timing, Stop to pause, Lap to record a split time without stopping, and Reset to clear everything. All lap times are shown below the main display with the total elapsed time for each.

    How to use

    Click Start to begin. While running, click Lap to record a split without stopping, or Stop to pause. Click Start again to resume. Click Reset to clear the display and all laps. Times are shown in hours:minutes:seconds.tenths format.

    Examples

    1 km run Start → run → Stop. Shows elapsed time to 0.1 s precision
    Lap recording Lap 1: 1:23.4 · Lap 2: 1:19.7 · Lap 3: 1:21.2
    Cooking timer use Start when food goes in → Stop when done → see elapsed

    FAQ

    How accurate is the stopwatch?

    It displays to 0.1-second precision and is based on performance.now() internally, giving sub-millisecond timing accuracy. Display updates happen every 100 ms.

    Does it work when the tab is in the background?

    The timer keeps running accurately — it uses wall-clock time not frame-based counting. However, the visual display may pause updating until the tab is active again.

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    Privacy and data handling

    This tool runs entirely in your browser. Nothing you type or paste is sent to any server — all processing happens locally on your device.