Stopwatch
Start, stop and lap a precise stopwatch in your browser, then copy or export your lap times.
00:00.00
Ready
Keyboard: S start / stop · L lap · R reset
Lap times
No laps yet — press Lap while the stopwatch runs.
| Lap | Lap time | Total time |
|---|
How it works
Press Start and the display counts up in hundredths of a second. Press Lap to record a split without stopping the clock — each lap shows both the time for that lap and the total elapsed time, with the fastest and slowest laps marked once you have two or more. Stop freezes the clock, Resume picks up where you left off, and Reset clears everything. The keyboard shortcuts S, L and R work anywhere on the page.
Timing is taken from the browser’s high-resolution clock: every reading is the difference between two timestamps rather than a count of ticks, so the elapsed time stays correct even if the tab is throttled in the background or the display repaints late. Copy your laps as plain text or download them as a CSV file for a spreadsheet. Everything runs in your browser — no account, no ads, and no times are sent anywhere.
Frequently asked questions
How accurate is this online stopwatch?
Every reading is the difference between two high-resolution browser timestamps, so the elapsed time is accurate to well under a hundredth of a second — the limit is your own reaction time on the Start and Stop buttons, not the clock. The display is rounded to 1/100 of a second.
Does the stopwatch keep running if I switch tabs or lock my screen?
Yes. The stopwatch stores the moment it started rather than counting ticks, so even if the browser throttles the tab in the background the total is still correct the moment you come back. It does keep running only while the page stays open — reloading the page resets it.
Can I record lap times and export them?
Press Lap (or the L key) while the clock runs to record a split; each lap shows its own time and the running total, with the fastest and slowest laps highlighted. Use Copy laps to put them on your clipboard as text, or Download .csv to open them in a spreadsheet.