Online Stopwatch
Time anything to the millisecond. Record laps, spot your fastest and slowest, and export the results.
Time anything, to the millisecond
Press Start to begin timing. The display shows minutes, seconds and milliseconds, with hours added once needed. Each press of Lap records the time for that lap and the overall split, and once you have at least two laps your fastest and slowest are highlighted.
How to use the stopwatch
- Press Start, or the Space bar.
- Press Lap (or L) at the end of each lap.
- Press Pause to stop, and Resume to carry on from the same time.
- Press Export CSV to download your laps for a spreadsheet.
- Press Reset (or R) to clear everything.
Lap time or split time?
A lap time is the length of a single lap. A split time is the total elapsed time when that lap ended. If you run three laps of 60, 62 and 58 seconds, the third lap time is 58 seconds and its split is 3:00. You can read more in how a stopwatch works.
About precision
The stopwatch uses the browser's high-resolution monotonic clock, so changes to your system clock do not affect it. It shows milliseconds, but the real limit is human reaction time, typically a couple of tenths of a second, plus small input delays. It is well suited to training and everyday timing, but not to officially timed events.
To count down rather than up, use the timer.
Frequently asked questions
What keyboard shortcuts are there?
Space starts or pauses, L records a lap, R resets and F toggles fullscreen.
Does it keep running in a background tab?
Yes. Elapsed time is measured from clock readings rather than by counting, so it stays correct even if the display updates less often.
Is my lap data saved?
Laps stay on the page until you reset or leave it. Export a CSV file to keep them.