StopwatchSTOPWATCH

Notices

Press Start or Space to run the stopwatch.

Press Lap or L to record a split. The fastest and slowest laps are marked on the board.

Press Pause, then Reset (R) to clear.

The stopwatch keeps running if you reload or close the tab by mistake and come back.

Times are measured with the browser's high-resolution clock and shown to the hundredth of a second. Below the board, each lap shows its own time and the running total.

Questions

Does the stopwatch keep running if I close the tab?

It remembers when you started. Open the page again and the elapsed time is correct, including the laps.

How precise is it?

The display updates about 60 times a second; the timing itself comes from performance.now(), which is precise to well under a millisecond. Human reaction time (about 0.2 s) is the real limit.

Can I copy my lap times?

Yes, select the lap table and copy it; it pastes cleanly into a spreadsheet.

What do the keyboard shortcuts do?

Space starts or pauses, L records a lap, R resets and F switches to full screen.