Online Stopwatch & Timer
Millisecond-accurate stopwatch with lap splits and countdown timer modes.
Frequently Asked Questions
How accurate is the stopwatch?
Uses performance.now() with requestAnimationFrame. Accuracy is typically ±1–2 milliseconds depending on browser and device load.
Does it run in the background?
Yes — timing is based on wall-clock deltas, so closing/reopening the tab or backgrounding it won't drift. The display updates once the tab becomes visible again.