Lap time vs. total time
Lap time is how long that lap took. Total (also called the split) is the time from the start to the moment you pressed Lap. Once you have three or more laps, the fastest lap is shown in green and the slowest in red.
How accurate is it?
The stopwatch reads your device’s high-resolution clock, so it doesn’t drift even if the browser slows down screen updates in a background tab. The real limit is your reaction time when you press the button — typically around two tenths of a second for a person responding to something they see.
Frequently asked questions
Does the stopwatch keep running if I close the tab?
No — closing the tab stops it. Switching to another tab is fine.
Can I use the keyboard?
Yes: Space starts and stops, L records a lap and R resets.
Last reviewed 2026-10-14.