Online stopwatch
Runs in this pageTime anything to a hundredth of a second, with laps that show both the split and the running total. Space starts and pauses; it keeps exact time even in a background tab.
0:00.00
Space starts and pauses, R resets. Keeps time correctly in a background tab; the alarm plays when the tab is open.
How to use it
- Press Start or Space.
- Press Lap to record a split; the list shows lap time and total.
- Pause, resume, or press R to reset.
Details
- Precision
- Displayed to 0.01 s, measured from the system clock
- Laps
- Unlimited, newest first, with split and total
- Keys
- Space start / pause, R reset
Questions
Does it need an account or send anything?
No. It runs in this page with your device's clock. Nothing is stored on a server.
How accurate is it?
It reads the system clock, so the total is as accurate as your device's clock; the display updates ten times a second. Human reaction time on the button (about 0.2 s) is the larger error.
Does it keep running if I close the tab?
No. Switching tabs is fine, but closing or reloading the page stops it.
Can I count down instead?
Use the Online timer for a countdown with an alarm.