Online Stopwatch

0:00.0
Press Start, or hit the space bar.

    Why this one does not drift

    A stopwatch that adds ten milliseconds on every tick slowly falls behind, because each tick arrives a little late and the errors accumulate. This one records when you started and asks the clock how long ago that was, so an hour-long run is still exact.

    Keyboard

    • Space — start or stop.
    • L — record a lap.
    • R — reset.

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    Free to use, no sign-up, works on any phone.

    Frequently Asked Questions

    How accurate is it?

    The elapsed time is worked out from the system clock each frame, not accumulated tick by tick, so it does not drift over long runs. The limit on accuracy is your own reaction time on the button, which is far larger than anything the timer contributes.

    Does it keep counting in a background tab?

    Yes. Browsers throttle animation in a hidden tab, but because the time comes from the clock, switching back shows the correct elapsed time immediately.

    What is the difference between a lap and a split?

    A lap is the time since the last lap button press; a split is the total elapsed at that moment. Both are shown for every lap, so you do not have to subtract by hand.

    Can I use the keyboard?

    Yes. Space starts and stops, L records a lap and R resets, so you can run it without looking away from what you are timing.

    Are my lap times saved?

    Only while the page is open. Nothing is stored or uploaded — reloading clears them, so copy anything you need to keep.

    Everything on this page runs inside your own browser. Nothing you type or upload is sent to a server, so your data never leaves your device.