About this tool
Keyboard shortcuts
- Space starts and stops the stopwatch.
- L records a lap while it is running.
- R resets it to zero.
- Shortcuts work with any keyboard layout, including Korean and Japanese input, and are ignored while you type in a text field.
Lap time vs. total time
Each lap row shows the lap time (time since the previous lap) and the total time when the lap was recorded. With two or more laps, the fastest and slowest laps are highlighted; if two laps tie, the earlier one is marked.
Accuracy and reloading the page
Time is measured with your browser’s high-resolution clock and shown to the hundredth of a second (digits are cut off, not rounded). Background tabs may update the display less often, but the measured time is not affected: it is recalculated as soon as you come back.
The state is saved on this device, so if you reload or accidentally close the tab, the stopwatch continues from where it would be, laps included.
Full screen for classes and workouts
Press Full screen to show the stopwatch large on a projector or a phone propped up during exercise. Press Esc or the button again to exit. The button is hidden on browsers that do not support full screen.