How to use the stopwatch
- Tap Start to begin timing.
- Tap Lap to record a split without stopping the clock.
- Tap Stop to pause, and Resume to carry on.
- Tap Reset to clear the time and laps.
On a computer, press the space bar to start and stop.
Reading lap times
Each lap row shows two times:
| Column | Meaning |
|---|---|
| +01:02.35 | The split: time since the previous lap |
| 03:15.80 | The total time when you tapped Lap |
The newest lap is at the top. Splits make it easy to compare laps on a running track, rounds of a workout or sections of a presentation.
How accurate is it?
The stopwatch measures time with your browser's high-resolution performance clock, which is precise to well under a millisecond, and shows hundredths of a second. Because it calculates elapsed time from the clock rather than counting ticks, it doesn't drift during long sessions.
If your phone slows the page down in the background, for example while you check a message, the display may pause, but the timing stays correct. When you return, it jumps to the true elapsed time.
Human reaction time is the biggest source of error in manual timing: tapping start and stop typically adds a tenth of a second or more. For competitions, use official timing equipment.
Ideas for using it
- Running and workouts: time intervals, laps and rest periods.
- Cooking: time steps that a recipe measures in minutes and seconds.
- Presentations and speeches: practise sections against a time limit. The word counter estimates speaking time for a script before you rehearse.
- Games and quizzes: time rounds or answers.
- Experiments: time reactions and simple science activities at school.
Tips
Keep the screen on during long timings; on Android, you can extend the screen timeout under Settings → Display. The stopwatch runs entirely in your browser and needs no internet once loaded.