Free Online Stopwatch with Lap Times
A premium online stopwatch with sub-millisecond accuracy. Press Start to count up, Lap to record split times, Reset to start over. Full-screen mode, keyboard shortcuts (Space / L / R) and a clean readable display work on every modern browser.
About the online stopwatch
An online stopwatch counts forward from zero with millisecond precision and lets you record split times — also called laps — without losing the running total. ClockAura's stopwatch runs entirely in your browser, so it starts the moment the page loads and never sends your timing data to a server. Athletes use it on the track, swimmers use it at the pool, photographers time long exposures with it, and parents reach for it when their kids ask 'how long can you hold your breath?' If you've ever wished your phone's stopwatch had a bigger display or worked with a keyboard, you'll feel right at home.
When to use the stopwatch
- Track running, swimming or cycling laps and compare your splits side by side.
- Time how long a presentation, speech or speech rehearsal really takes.
- Measure how long a recipe step takes — useful for blogging or YouTube cooking videos.
- Record reaction-time experiments, science-fair demos and classroom games.
- Time long-exposure photographs, light-painting sessions and astrophotography setups.
- Track how long the kids spend on a chore or a video-game session.
- Measure rest periods between sets at the gym without a dedicated app.
- Run a friendly contest at a party — fastest puzzle, longest plank, fastest typist.
How to use the stopwatch
- Press the big Start button or hit the Spacebar to begin counting up.
- Press Lap (or the L key) at any time to record a split — your previous laps stay visible below.
- Pause to stop the count temporarily; press Start again to resume from where you left off.
- Hit Reset (or R) to clear the elapsed time and start over from 00:00.000.
- Use the Full screen button if you want a giant display you can read from across the room.
Tips for getting the most out of the stopwatch
- Keep the tab in the foreground for the smoothest update — most browsers throttle background tabs to save power.
- Use the keyboard shortcuts so you do not have to click — Spacebar to start/pause, L for lap, R for reset.
- Cast or mirror your screen to a TV when running classroom relays so the whole class can see.
- On phones, tap the Full screen button to lock the orientation and avoid accidental swipes.
- Bookmark the page — it loads instantly the next time you need it, and it works offline once cached.
Stopwatch FAQ
How accurate is this online stopwatch?
ClockAura's stopwatch reads from your device's high-resolution performance clock. On a foreground tab, accuracy is typically within a few milliseconds — comparable to a digital wristwatch and good enough for school sports, gym sessions and casual measurements.
Will my time keep counting if I switch tabs?
Yes. The elapsed time is calculated from absolute timestamps, so even if your browser pauses background animations, the stopwatch shows the correct total when you come back to the tab.
Can I record more than one lap?
Yes — there is no limit. Each lap is added to the list with its own number so you can scroll back through every split you took during the session.
Does the stopwatch work offline?
Yes. After your first visit the page is cached by your browser; you can reopen it on a flight or anywhere without signal and it'll still run.
Is there a keyboard shortcut to start the stopwatch?
Press Spacebar to start or pause, L to record a lap and R to reset. The shortcuts work whenever the page is focused and you are not typing into an input.