Free Online Stopwatch
Precise stopwatch with lap time recording. Start, pause, resume and reset with keyboard shortcuts. Track your best and worst laps instantly.
Space = Start/Stop | L = Lap | R = Reset
Lap Times
| # | Lap Time | Total Time |
|---|
About the Stopwatch
This free online stopwatch uses the browser's high-precision performance.now() API to measure time accurately to the millisecond. Unlike system clocks that can drift, performance.now() provides a monotonically increasing counter unaffected by system clock changes.
The lap feature records individual segment times alongside the running total, making it ideal for timing sports events, experiments, cooking, presentations and any activity requiring interval tracking.
How to Use the Stopwatch
Start the Timer
Click "Start" or press Space to begin counting. The display updates in real time.
Record Laps
Click "Lap" or press L to record an interval. Best and worst laps are highlighted automatically.
Pause / Resume
Click "Start" again or press Space to pause. Press again to resume from where you left off.
Reset
Click "Reset" or press R to clear the timer and all lap records.
Frequently Asked Questions
The timer uses performance.now() which is accurate to sub-millisecond resolution (typically within 0.1 ms). The display shows centiseconds (1/100th of a second).
Yes — the elapsed time is calculated from a start timestamp rather than counting intervals, so accuracy is maintained even when the tab is in the background.
There is no fixed limit. You can record hundreds of laps; the table is scrollable.
You can select all the text in the lap table and copy it. A CSV export feature is planned for a future update.