Stopwatch
Time to the hundredth of a second with laps; the fastest and slowest laps are marked.
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Runs in this page in your browser; nothing is uploaded.
About this tool
Time a run, a speech, a presentation rehearsal or a lab step, and record laps as you go. The stopwatch shows minutes, seconds and hundredths of a second, and adds hours once an hour has passed.
Each lap shows its own time and the running total, and with two or more laps the fastest and slowest are marked. Copy the laps as a tab-separated list to paste into a spreadsheet. It runs in your browser and nothing is uploaded or saved, so reloading the page clears it.
How to use it
- Select “Start” to begin timing.
- Select “Lap” to record a lap while the stopwatch runs. The newest lap appears at the top of the table.
- Select “Pause” to stop and “Resume” to carry on from the same time.
- Select “Copy laps” to copy the table, or “Reset” to clear the time and all laps.
Common questions
Does it keep counting in a background tab?
Yes. Time is measured from the browser’s high-resolution clock (performance.now), not by counting screen refreshes, so switching tabs does not lose time and the display catches up when you come back. Closing or reloading the page resets it, because nothing is saved.
How precise is it?
The time is shown to a hundredth of a second, and each lap reads the clock at the moment you press “Lap”. Your own reaction time affects the result more than the clock does.
How are the fastest and slowest laps chosen?
A lap time is the time since the previous lap, or since the start for the first lap. Once there are at least two laps, the rows with the shortest and longest lap times are highlighted.
What does “Copy laps” copy?
One line per lap, oldest first, with the lap number, the lap time and the total separated by tabs, so it pastes into separate spreadsheet columns.
Can I record a lap while paused?
No. “Lap” works only while the stopwatch is running. Pausing keeps the time and the laps; only “Reset” clears them.
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