Online Stopwatch with Lap Timer
Track time precisely with lap splits and export functionality. Perfect for sports timing, workouts, and performance measurement.
Runs in your browser. No data leaves your device.
Frequently Asked Questions
How does the Stopwatch work?
On start, the tool stores an anchor timestamp via Date.now() minus any previously paused elapsed time. A fast interval tick continuously sets elapsedTime = Date.now() - startTime, so accuracy is tied to wall-clock timestamps rather than interval count. Lap splits are computed by subtracting the previous lap's cumulative time from the current elapsed time.
How accurate is the online stopwatch?
It uses your browser's high-resolution timer (performance.now), which is accurate to the millisecond. This is more than precise enough for sports timing, cooking, and general use.
Can I record lap times?
Yes. Press the Lap button while the stopwatch is running to record a split time. All laps are listed with individual and cumulative times, and you can export them.
Does the stopwatch keep running if I switch tabs?
Yes. The stopwatch tracks elapsed time based on timestamps, not intervals, so switching tabs or minimizing the browser does not affect accuracy.