Stopwatch
Measure elapsed time with a free online stopwatch. Record lap and split times, pause and resume, and download your laps as a CSV file.
Press Start to begin timing.
Your laps
| Lap | Split | Total |
|---|
Split and total: reading the lap table
Each press of Lap adds a row with two times. Split is the time since your previous press, and Total is the time since you started. A runner who covers three laps of a track in 1:32, 1:35 and 1:31 sees those three figures in the Split column and 1:32, 3:07 and 4:38 in the Total column. The split shows how steady the pace is; the total shows where you stand overall. The newest lap is always at the top.
How precise the stopwatch is
The display shows hundredths of a second, and exported laps carry thousandths. Elapsed time comes from a steadily increasing clock inside the browser, not from the time of day, so an automatic clock correction or a daylight-saving change in the middle of a run does not disturb the result. The weaker link is the person pressing the button. Reacting to something you see takes roughly a fifth of a second, which is why hand-timed results in athletics are recorded only to a tenth. What a second actually is, is the subject of the atomic second.
Exporting your laps
“Export laps” downloads a CSV file that opens in Excel, Google Sheets, Numbers or any text editor. It has three columns: the lap number, the split in seconds and the total in seconds, each with three decimals, ready for averages or a chart. You can record up to 1,000 laps in a session. Nothing is uploaded, and nothing is stored: reloading or closing the page clears the session, so export before you leave.
Questions and answers
Does the stopwatch keep running in a background tab?
Yes. The display stops redrawing while the tab is hidden, but the elapsed time is calculated from the browser’s clock, so the figure is right when you come back. If the device itself goes to sleep, that clock may pause on some systems; keep the device awake for long measurements.
Can I time more than an hour?
Yes. After 59:59 the display adds an hours column and keeps counting for as long as the page stays open.
Should I use the stopwatch or the timer?
Use the stopwatch to find out how long something takes; it counts up from zero. Use the countdown timer when the duration is known in advance and you want a signal at the end.
Calculations run in your browser. No account is needed, and your inputs are not sent to our server. Read how our clocks work.