Stopwatch
A precise online stopwatch with lap times — start, pause, lap and reset, with drift-free timing anchored to the system clock.
Press Lap while running to split the current total into segments — each row shows the segment time and the running total.
The stopwatch is anchored to the wall clock, so it keeps counting if you switch tabs; rendering just catches up when you come back. Times show minutes:seconds.centiseconds.
This tool runs entirely in your browser. Your data never leaves your device — it is not uploaded to any server.
How to use
- 1Click Start to begin timing.
- 2Click Lap to record a split without stopping the clock.
- 3Pause, resume or reset at any time.
Stopwatch
Measures elapsed time to the hundredth of a second using the system clock rather than accumulated intervals, so it stays accurate even when the browser throttles a background tab.
Record laps while running; each lap shows its own split and the running total, and the display uses large tabular digits so splits stay readable at a glance.
Frequently asked questions
Is it accurate?
Yes — elapsed time is derived from Date.now() against a fixed start timestamp, not accumulated timer callbacks, so background-tab throttling cannot cause drift.
Do laps survive a page reload?
No — like a physical stopwatch, resetting or reloading clears the session. Keep the tab open to preserve laps.
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Embed this tool
Put this tool on your own site with one line — it runs entirely in the visitor's browser.
<iframe src="https://zoyku.com/en/tools/stopwatch?embed=1" width="100%" height="640" style="border:0;border-radius:16px" title="Zoyku — stopwatch" loading="lazy"></iframe>