How to use Online stopwatch
- 1
Start timing
Press Start or the space bar; the digits count up in minutes, seconds and hundredths, adding hours after the first hour.
- 2
Record laps
Press Lap, or the L key, each time a runner passes, a slide changes or a round ends; the clock keeps running.
- 3
Stop and resume
Stop pauses the count without losing it, Resume continues from the same point, and Reset clears time and laps.
- 4
Export the laps
Download a CSV with lap number, lap time and running total, or copy the table and paste it into a spreadsheet.
Limits and Pro
Free with no sign-up: 1 stopwatch with unlimited laps, a display to 0.01 s, 1 ms values in the CSV export, and timing that keeps going across reloads.
About Online stopwatch
This stopwatch is built for timing things that happen in parts: intervals on a running track, rounds in a board game, how long each speaker takes in a meeting, or each step of a recipe. Every time you press Lap it stores the moment as a split, the total time since you started, and shows the lap time, the time since the previous split. With three or more laps the fastest is marked in green and the slowest in red, so uneven pacing stands out without any maths.
Time is measured from the system clock rather than by counting ticks, which matters for long sessions. A stopwatch that adds up interval callbacks drifts when the browser slows a background tab; this one subtracts two clock readings, so an hour-long recording is still right when you come back to it. The state is saved in your browser as it changes: reload the page, or close and reopen the tab, and a running stopwatch is still running with all its laps.
The export is a plain comma-separated file with columns for the lap number, the lap and total times as text, and both values again in milliseconds for calculations. The display can go full screen for a room to see.
It is a single stopwatch: there is no countdown on this tab, no official race timing with photo finish or chip readers, and no sync between devices.
Privacy
The stopwatch runs only in this browser. Start times and laps are kept in local storage on this device so they survive a reload, and the CSV is generated on your computer; nothing is sent to a server.