Millisecond precision • Lap timing • Keyboard shortcuts
How precise is this stopwatch?
The stopwatch uses requestAnimationFrame and Date.now() for sub-10ms precision. It displays up to hundredths of a second (10ms resolution) in the display.
What are the keyboard shortcuts?
Space bar starts/stops the timer. L records a lap while running. R resets the timer when stopped.
What is a split time?
Split time (shown in the Lap column) is the time taken for that individual lap — the difference between when this lap started and ended.
How does +/- Average work?
It shows how each lap compares to your average lap time. Green means faster than average, red means slower.
Can I use this in fullscreen?
Yes. Click the fullscreen button in the header to expand the timer. This is useful for racing, presentations, or gym workouts.
How do I export lap times?
Click Export in the header to download a CSV file with all lap labels, split times, and total elapsed times.
Does the timer continue if I switch tabs?
Yes. The timer uses Date.now() as its reference clock, so it continues accurately even when the tab is not active.
Is there a limit to how many laps I can record?
There is no practical limit. Laps are stored in memory for the current session. Resetting clears all lap data.