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Stopwatch Tool

A high-precision stopwatch with start/stop, lap and reset. Keyboard controls supported, and everything runs in your browser.

Last updated: 2026/10/16 Utility Feedback & bug reports
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Laps

No laps yet. Press "Lap" while the timer is running to record one.

How to Use

1

Start the timer

Press the "Start" button or the Space key to begin. Elapsed time is displayed in real time down to 1/100 of a second.

2

Record laps

While running, press the "Lap" button or the L key to record the current lap time and total time in the list.

3

Stop & reset

Use "Stop" to pause and "Resume" to continue. Press "Reset" or the R key to clear the timer and all laps.

Keyboard Shortcuts

  • SpaceStart / Stop
  • LRecord lap
  • RReset

About the Stopwatch

A stopwatch is a web tool for measuring elapsed time with high precision. This tool uses the browser's high-resolution timer (performance.now), so it measures time more accurately than a typical seconds display. Use it for sports timing, study and work sessions, cooking and experiment intervals, and more. All processing happens entirely in your browser, and no data is ever sent to a server.

Features

  • High PrecisionMillisecond-accurate timing powered by performance.now, designed so errors do not accumulate even over long sessions.
  • Lap TimingRecords lap times and total times together, automatically highlighting the fastest and slowest laps.
  • Keyboard ControlSpace to start/stop, L to lap, R to reset. Operate quickly without using the mouse.
  • Privacy ProtectedAll processing happens in your browser. Timing data is never sent to any server.

Use Cases

  • Timing and laps for running, swimming and other sports
  • Tracking study, work and meeting time
  • Interval timing for cooking and experiments
  • Checking pacing for presentations and speeches
  • Records challenges for games and typing

FAQ

Is the stopwatch free to use?
Yes, it is completely free. No registration or installation is required—just open it in your browser and start.
How accurate is the timing?
It uses the browser's high-resolution timer (performance.now) and displays time down to 1/100 of a second (10 ms). Elapsed time is calculated from a reference timestamp, so errors do not accumulate even if display updates are delayed.
Can I control it with the keyboard?
Yes. Use Space to start/stop, L to record a lap, and R to reset. Make sure no input field is focused when using shortcuts.
Can I copy the lap times?
Yes. The "Copy Laps" button copies all recorded lap times and total times to your clipboard as text.
Does timing continue if I switch tabs or leave the page?
While running, time is calculated from a reference timestamp, so switching tabs is fine—the correct elapsed time is shown when you return. However, reloading the page resets the timer.
Is my timing data stored or sent anywhere?
No. All processing happens locally in your browser, and timing data and lap records are never sent to or stored on a server.

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