Online Stopwatch
Start, stop and record laps with millisecond precision. The fastest and slowest laps are highlighted automatically. Export your laps as CSV.
Times stay in your browser. Nothing is uploaded.
How to use this stopwatch
- Click Start to begin. The display updates in real time with millisecond precision.
- Click Lap to record split times — each lap shows its duration and the running total.
- Click Stop to pause, then Start again to resume from where you stopped.
- Copy laps to clipboard or export as CSV with one click.
Frequently asked questions
How precise is the stopwatch?
It uses your browser's high-resolution performance clock, accurate to a millisecond. Display updates every animation frame (~60 fps).
What does Lap do?
Lap records the current elapsed time and starts a new split. Each lap shows its individual duration and the cumulative total.
Are fastest and slowest laps highlighted?
Yes. With two or more laps, the fastest is shown in green and the slowest in red.
Can I export the laps?
Yes. Click Download CSV to save a spreadsheet-friendly file, or Copy laps for the clipboard.