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    Stopwatch

    Precise online stopwatch with lap times. Start, stop, and record splits, all in your browser.

    Free to use. Runs in your browser.

    Start, stop, and lap a stopwatch with millisecond precision. Records lap times and total elapsed time entirely in your browser.

    00:00.00

    How This Stopwatch Works

    This stopwatch uses requestAnimationFrame and performance.now(), the highest-precision timing APIs available in a browser. It updates every frame (~60 times per second), giving you centisecond accuracy (hundredths of a second).

    The lap feature records the elapsed time at the moment you press it, without pausing the main timer. You can record as many laps as you want, and they're displayed in reverse chronological order so the most recent lap is always at the top.

    Everything runs in your browser's memory, there's no server, no account, and no data persistence. If you navigate away from the page, the timer resets. For permanent time tracking, export your laps with the Copy button before leaving.

    Time Format Reference

    DisplayMeaningExample Use
    00:05.235 seconds, 23 centisecondsShort sprints, reaction tests
    02:30.002 minutes, 30 secondsExercises, presentations
    15:00.0015 minutes exactlyPomodoro-style work blocks
    1:00:00.001 hourLong tasks, study sessions

    What this means for you: The format is MM:SS.cs (minutes, seconds, centiseconds). Hours appear automatically when elapsed time exceeds 60 minutes.

    Common Uses for a Stopwatch

    Workout Timing

    Time rest periods between sets, HIIT intervals, or total workout duration. Lap function tracks individual set times without stopping the clock.

    Cooking

    Time steeping, blanching, resting, and other short cooking intervals that don't need a full countdown timer, just a quick "how long has it been?"

    Presentations & Speeches

    Track how long your presentation runs. Use laps to mark section transitions so you can see which parts are running long.

    Performance Testing

    Time how long manual processes take, page loads, form completions, onboarding flows, to benchmark user experience improvements.

    Stopwatch vs Timer: Which Do You Need?

    Stopwatch (count up)

    • Measuring how long something takes
    • Recording lap splits for comparison
    • Open-ended tasks with no set duration

    Timer (count down)

    • Fixed-duration tasks (cooking, exercise)
    • Pomodoro work sessions (25 min blocks)
    • When you need an alarm at the end

    Related Tools

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    Countdown Calculator

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    Work Hours Calculator

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    Typing Speed Test

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    Time Zone Converter

    Convert times between time zones

    Speed Distance Time Calculator

    Calculate speed, distance, or time

    How to use this tool

    1

    Click Start to begin timing

    2

    Press Lap to record split times while the timer runs

    3

    Click Pause to stop, then Copy Laps to export your times

    Common uses

    • Timing workout intervals and rest periods
    • Recording presentation and speech durations
    • Benchmarking task completion times
    • Tracking cooking intervals and preparation steps

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    Frequently Asked Questions

    How accurate is this stopwatch?
    It uses requestAnimationFrame with performance.now() for ~16ms precision (centisecond accuracy). Suitable for most timing needs outside competitive sports.
    Do laps persist if I leave the page?
    No. The stopwatch runs in-browser memory only. Use the Copy Laps button to save your times before navigating away.
    Can I export lap times?
    Yes. Click Copy Laps to copy all lap times to your clipboard as formatted text. Paste into any document or spreadsheet.
    Does it work in the background?
    requestAnimationFrame pauses when the tab is hidden, but the elapsed time is calculated from absolute timestamps, so the display catches up when you return.
    Can I use this on mobile?
    Yes. The stopwatch works on all modern mobile browsers. The large display is designed to be readable at a glance.
    What's the maximum time it can track?
    There's no practical limit. It displays hours, minutes, seconds, and centiseconds. The format extends to show hours when elapsed time exceeds 60 minutes.
    Is there a countdown timer instead?
    This is a stopwatch (counts up). For counting down to zero, use our Pomodoro Timer or Countdown Calculator.
    Can I pause and resume?
    Yes. Click Pause to freeze the timer, then Resume to continue from where you left off. The elapsed time is preserved accurately.
    How do laps work?
    Each lap records the total elapsed time at the moment you press Lap. The timer continues running. Laps appear in reverse order (newest first).
    What's the difference between lap and split?
    In this tool, laps show cumulative elapsed time. To calculate individual interval durations, subtract consecutive lap times.
    Is any data sent to a server?
    No. The stopwatch runs entirely in your browser using JavaScript timing APIs. Nothing is transmitted or stored.
    Can I use keyboard shortcuts?
    Currently the controls are button-based. Use Tab to navigate and Enter/Space to activate buttons for keyboard-only operation.

    Results are for general informational purposes only and should be checked before use. They are not professional advice. See our Disclaimer and Terms of Service.