Measure elapsed time with sub-millisecond precision using the browser High Resolution Performance API. Features intuitive Start, Pause, and Lap logging with real-time split comparisons.
Runs entirely in your browser
A precise stopwatch for timing anything — a workout, a task, a process, a race. It measures elapsed time using the browser’s High Resolution Performance clock, which gives sub-millisecond precision rather than the coarse ticks of an ordinary timer, and offers the controls you expect: start, pause, resume and lap.
The lap feature records split times as you go and compares them in real time, so you can see whether each interval was faster or slower than the last. That makes it genuinely useful for interval training, benchmarking a repeated task, or timing anything where the pattern of splits matters as much as the total.
It runs entirely in your browser with no account, so you can start timing immediately and nothing is uploaded. Keep the tab open and it keeps running as a live stopwatch.
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