Stopwatch

Online stopwatch with Start, Stop, Reset and LAP buttons. Shows time to 1/100 second with a table of lap and total times, and keeps running if you reload. Timing is based on the clock time when you pressed Start, so it stays accurate in a background tab.

About this tool

What does this stopwatch do?

It measures elapsed time and records laps, displayed as hours, minutes, seconds and hundredths (HH:MM:SS.cc). Each lap row shows both the time of that lap and the total time since the start, so you can track intervals in a run, a workout, a presentation or a cooking step.

How to use

  1. Click Start to begin timing.
  2. Click LAP while it is running to record a lap. The newest lap appears at the top of the table.
  3. Click Stop to pause. Click Start again to continue from the same time.
  4. Click Reset (available while stopped) to clear the time and all laps.

Features

  • Display to 1/100 second
  • Unlimited laps, with lap time and total (split) time for each
  • The current, still-running lap is shown in the first row
  • Keeps counting through page reloads, closed tabs and background tabs, because the start time and laps are saved in this browser
  • Large, monospaced digits that do not jitter while counting

Lap time vs total time

NoLap timeTotal time
300:00:12.40 (running)00:01:02.90
200:00:25.3000:00:50.50
100:00:25.2000:00:25.20

Lap time is the time since the previous lap. Total time (also called split time) is the time since you first pressed Start.

FAQ

Does it keep running if I close or reload the page?

Yes. The stopwatch saves the moment you pressed Start, so when you open the page again it calculates the elapsed time from that moment and continues. Laps are saved too.

How accurate is it?

Elapsed time is calculated from your device's clock, not by counting timer ticks, so it does not drift when the browser slows down hidden tabs. Changing the system clock while timing will affect the result.

Can I count down instead?

No. This tool only counts up. It has no countdown timer or alarm.

Can I export the lap times?

There is no export button. You can select the table and copy it.

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