Stopwatch
Precise stopwatch with lap splits and millisecond accuracy.
Controls
Keyboard Shortcuts
How It Works
The stopwatch uses performance.now() for high-resolution timing and requestAnimationFrame for smooth visual updates at 60fps. The elapsed time is always derived from the difference between the start timestamp and now, so it remains accurate even if the tab loses focus.
Features
- ✓ Centisecond precision display
- ✓ Unlimited lap recording
- ✓ Best / Worst lap highlighting
- ✓ Keyboard shortcuts (Space, L, R, F)
- ✓ Full-screen mode for presentations
Disclaimer: For informational purposes only.
About the Stopwatch
This stopwatch handles date arithmetic, time zones, calendars, and scheduling utilities. Precise stopwatch with lap splits and millisecond accuracy.
Use for planning events, deadlines, workdays, and time-zone aware calculations.
Adjust the inputs above to model your specific scenario with the Stopwatch.
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