Online Stopwatch
A precise online stopwatch with lap times, best/worst lap tracking, and keyboard shortcuts.
Space start/stop · L lap · R reset
| # | Lap Time | Total | |
|---|---|---|---|
| Best Slow |
How It Works
Click Start to begin timing or press Space. Click Lap (or press L) to record a split time without stopping the clock. Click Stop to pause, then Start again to resume. Reset clears everything. The lap table shows each split with best and worst laps highlighted.
**Online Stopwatch — Millisecond Precision in Your Browser**
A stopwatch should be instant, accurate, and always available. Our browser-based stopwatch loads in milliseconds — no app download, no login, no configuration. Click Start and time anything.
**Millisecond Precision**
The display updates every animation frame (~60 times per second) for smooth millisecond readout. The timing engine uses the browser's high-resolution performance API, accurate to sub-millisecond, so your splits are genuine.
**Lap Times**
Each lap records the individual split time (time since the last lap) and the cumulative total. The lap table automatically highlights your fastest lap in green and slowest in red — immediately useful for sports intervals, experiment timing, or study sprints.
**Keyboard Shortcuts**
- **Space** — Start / Pause (toggle)
- **L** — Record a lap while running
- **R** — Reset when paused
**Continues When Tab is Minimised**
The stopwatch keeps running accurately when you switch to another tab or minimise the browser. The time is calculated from a reference timestamp, not incremented by a counter — so no drift.
**Common Uses**
- **Sports and fitness** — Sprint times, swim laps, interval training
- **Cooking** — Precise timing for multiple dishes without watching the clock
- **Studying** — Time each subject or topic during a revision session
- **Presentations** — Track section durations during rehearsal
- **Science experiments** — Reaction times, experiment durations, event timing
- **Games** — Speed runs, puzzle times, head-to-head challenges