Stopwatch
Start, lap, stop — to the hundredth of a second.
00:00.00
Nothing leaves your device
This tool runs entirely in your browser. What you type, play or record here stays on your device: nothing is uploaded or saved on a server.
How it works
- Press Start (or the space bar) to begin timing.
- Press Lap (or L) to record a lap: each shows its own time and the total so far.
- Pause to stop the clock, Resume to go on, Reset to clear it.
Frequently asked questions
- How precise is it?
- It shows hundredths of a second and reads your device’s clock, so it does not drift. Your reaction time pressing the button is the real limit — about a fifth of a second.
- Does it keep time in another tab?
- Yes. The time is worked out from the clock, not by counting ticks, so it stays right in a background tab or after the laptop sleeps, and the sound is scheduled ahead so it rings on time.
- Can I show it on a projector?
- Press Full screen (or F): the digits fill the screen, big enough for a classroom or a meeting room. Press Esc to leave.
- Are there keyboard shortcuts?
- Space starts and pauses, R resets, F switches full screen and L records a lap on the stopwatch.
- Is anything uploaded?
- No. The timer runs in your browser; nothing is sent anywhere.