Online Stopwatch
A precise online stopwatch with lap splits — start it in a single tap.
Tip: tap the time to start or pause.
How to use the stopwatch
- 1
Press the big Start button to begin timing — the clock counts up to the hundredth of a second.
- 2
Hit Lap to record a split. The lap list shows each segment plus the running total.
- 3
Use Pause to freeze the time, then Start again to resume exactly where you left off.
- 4
Press Reset to clear the stopwatch and wipe the lap list.
- 5
Tap the fullscreen icon for a giant display you can read from across the room.
Tips & tricks
This stopwatch is built for accuracy. It measures time with the browser's high-resolution clock, so it stays correct even if you switch tabs, lock your phone, or leave it running for hours — there is no slow drift like older JavaScript timers.
The lap feature is the real workhorse. Each lap row shows the split (the time for that segment) and the total elapsed time, and the fastest and slowest laps are highlighted automatically — making it easy to spot your best interval in a workout or the slowest step in a process.
Everything runs in your browser: nothing is uploaded and no account is needed. Leave the tab open in the background and the time keeps counting correctly. On phones, add the page to your home screen for a one-tap stopwatch.
Frequently asked questions
Is this online stopwatch accurate?
Yes. It uses the browser's high-resolution performance clock as the source of truth, not a simple interval, so it does not drift even over long sessions or when the tab is in the background.
Does the stopwatch keep running if I switch tabs or lock my phone?
Yes. The elapsed time is calculated from real timestamps, so when you return to the tab the display instantly snaps to the correct time — the count is never lost.
How do lap times work?
Press Lap while the stopwatch runs to capture a split. Each entry shows the time for that segment and the cumulative total, and your fastest and slowest laps are highlighted.
Can I use the stopwatch in fullscreen?
Yes. Tap the fullscreen button for a large, high-contrast display that is easy to read from a distance — useful for classrooms, gyms and group activities. Press Escape to exit.
Do I need to install anything or sign up?
No. The stopwatch runs entirely in your browser with no download, no account and no tracking cookies. It works on any modern phone, tablet or computer.
Why does the stopwatch show milliseconds?
It displays time down to a hundredth of a second so you can capture precise splits for sports, science experiments, cooking and timing tasks. Fixed-width digits keep it readable at a glance.
Is the online stopwatch free?
Completely free, with no limits on how long you run it or how many laps you record.
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