How to use
- Press Start (or Space) and the time counts up in hundredths of a second.
- While it runs, press Lap (or L) to record a split at that moment.
- Stop (Space) pauses it, and Resume carries on from where you left off. Reset (R) clears the time and all laps.
- Copy laps copies a tab-separated table you can paste straight into Excel or Google Sheets.
Lap time vs total time
| Column | Meaning | Example |
|---|---|---|
| Lap time | Time since the previous lap | how long the second lap alone took |
| Total | Time since the start | start to the end of lap two |
| Fastest / Slowest | Shortest and longest lap time, once you have two or more laps | spotting where your pace dropped |
If you press Lap at 1:20, 2:45 and 4:00, the lap times are 1:20.00, 1:25.00 and 1:15.00 — lap 3 is marked fastest and lap 2 slowest.
Accuracy
- Time comes from the browser’s high-resolution clock (
performance.now()) as the difference from the moment you pressed Start. The display redraws every frame, but switching tabs or a brief freeze does not add drift. - Digits below 1/100 s are truncated, not rounded: 12.349 s shows as 12.34 s.
- Human reaction time on the button (typically 0.1–0.3 s) affects every stopwatch. Use dedicated timing equipment for official results.
Things to keep in mind
- Shortcuts work whenever the cursor is not in a text box. Space always starts and stops the stopwatch, even if a button has focus.
- Refreshing or closing the page clears your laps, so copy them first.
- To work in focused intervals, try the Pomodoro timer. To find the gap between two clock times, use the time difference calculator.
FAQ
Does it keep counting if my phone screen turns off?
Yes. Because elapsed time is measured from the start moment, the time that passed while the screen was off is included when you come back — unless the browser discards the page entirely.
Can it run for more than an hour?
Yes. Past one hour the display adds an hours field, like 1:02:03.45.
Are my times saved anywhere?
No. Everything stays on this page and nothing is sent to a server.