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PRODUCTIVITY

Stopwatch

Track time with an online stopwatch. Features include start, stop, lap, and reset.

Tool statusRuns in your browser
Preview

Stopwatch

00:00.00

Laps

No laps yet.

How it works

  1. Enter your input

    Fill in the values, paste your text, or upload the file this tool works with.

  2. See results instantly

    Most tools update live as you type; a few use a single button. Either way, the result appears right on this page.

  3. Use your results

    Copy, download, or share what the tool produces — you're always in control of the output.

Privacy and processing — Runs locally in your browser. This tool does not upload your input.

What is Stopwatch?

A precise, browser-based stopwatch with start, stop, lap, and reset — nothing to install, nothing sent anywhere.

UNDERSTAND THE TOOL

How to use the online stopwatch

Features

  • Start / Resume and Stop to control timing.
  • Lap to record a split without stopping the clock.
  • Reset to clear the time and lap list.

Accuracy

The stopwatch measures real elapsed wall-clock time on every tick rather than simply counting fixed intervals, so it stays accurate even if the browser tab is briefly throttled in the background. Once the elapsed time passes an hour, an hours segment appears automatically instead of the display wrapping back to zero.

Limitations

Timing only runs while this page stays open. Closing the tab or reloading resets it — there is no server-side timer to fall back to, by design, since nothing about your session is sent anywhere.

Display format

Elapsed time is formatted as MM:SS.cc until an hour passes. After that, it displays HH:MM:SS.cc.

After one hour

3,723,450 ms displays as 01:02:03.45.

HH:MM:SS.cc

Stopwatch state

Lap times live only in the current browser tab. Closing or refreshing the page clears the running time and recorded laps.

Frequently Asked Questions

Does it keep running if I switch tabs?

Yes. It tracks real elapsed time rather than counting ticks, so switching tabs or briefly minimizing the window doesn't throw off the reading.

Can it track more than an hour?

Yes, an hours segment (HH:MM:SS) appears automatically once the elapsed time passes 60 minutes, and it keeps counting beyond 24 hours if needed.

Is my timing data saved anywhere?

No. Everything lives only in this page's memory and disappears when you close or reload the tab.

How are lap times calculated?

Each lap records the elapsed time at that moment. The display keeps total elapsed time and the lap list separately.

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