Online Stopwatch
Precise stopwatch with milliseconds and lap timing in browser
About this tool
This free online stopwatch gives you precise timing down to hundredths of a second, right in your web browser. Hit Start to begin, Lap to record split times without stopping, Pause to freeze the clock, and Reset to clear everything. No app to download, no account to create — it just works.
The lap timing feature is particularly useful for sports and exercise: record splits for each lap of a track, each set in a gym workout, each round of an interval training session, or each segment of a race. The best and worst laps are highlighted automatically so you can spot your strongest and weakest performances at a glance.
Beyond sports, online stopwatches are used in classrooms (timing student presentations, quiz rounds, or experiments), professional cooking (holding exact rest times or precision timings in recipe testing), board games and quiz nights (timed rounds), and scientific experiments where a physical stopwatch isn't available. The browser-based format means it's accessible from any device with a screen.
The stopwatch uses the browser's performance.now() API for high-resolution timing, which provides sub-millisecond accuracy independent of system load. The display updates every ~50ms so you see smooth hundredths-of-a-second movement without consuming excessive CPU.