Online stopwatch
Measure elapsed time precisely and record laps while the stopwatch keeps running.
00:00
Ready to start
How the stopwatch works
The stopwatch counts the time elapsed since you press 'Start'. You can pause it at any time and resume from where you left off.
The 'Lap' button records the accumulated time at that instant without stopping the stopwatch, useful for measuring segments of a race or exercise repetitions.
Unlike a countdown timer, a stopwatch has no preset limit: it's for when you don't know how long something will take and want to measure it precisely, like actual study time, a work call, or a training session with variable-length sets.
Worked example
If you start the stopwatch and press 'Lap' at 0:45 and again at 1:30, you'll see both marks in the lap list while the total time keeps running. In athletics, this lap function is the same one coaches use to record each 400-meter split during an interval session.
Frequently asked questions
- Does the stopwatch keep running if I switch tabs?
- Yes. The time is calculated from the system clock, so it stays accurate even if the tab is in the background.
- Can I save the laps when I'm done?
- Laps remain visible on screen as long as you don't reset the stopwatch; they can't be exported to a file at this time.
- How many laps can I record?
- There's no practical limit: you can press 'Lap' as many times as you need.
- How is this different from a countdown timer?
- A stopwatch counts up from zero with no preset limit, while a countdown timer counts down from a duration you define in advance.