Online Stopwatch — Full Screen, With Laps
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
A stopwatch counts UP from zero (a timer counts down to zero). Press Start to begin, tap Lap to record a split without stopping the clock, and Stop to finish. ClockAura's stopwatch is accurate to a few milliseconds using the browser's high-resolution performance clock, and keeps running even if you switch tabs.
This stopwatch counts up from zero in milliseconds and records laps without stopping the running total. It runs entirely in your browser, starts as soon as the page loads, and never sends your times to a server. It has a bigger display than a phone stopwatch and works from the keyboard — handy on the track, at the pool, for long photo exposures, or for 'how long can you hold your breath?'
Lap vs split time (example: three 400m runs)
| Term | What it measures | Example |
|---|---|---|
| Lap time | Time for that one lap alone | Lap 2 = 1:32 |
| Split time | Total elapsed at that point | At lap 2 = 3:01 |
| Final time | Full running total at the end | Final = 4:35 |
When to use the stopwatch
- Track running, swimming or cycling laps and compare your splits side by side.
- Time how long a presentation or speech rehearsal really takes.
- Record reaction-time experiments, science-fair demos and classroom games.
- Time long exposures and light-painting shots.
- Measure rest periods between sets at the gym without a dedicated app.
- Run party contests — 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 L) to record a split; earlier laps stay listed below.
- Pause to stop the count; press Start again to resume.
- Hit Reset (or R) to clear the elapsed time and start over from 00:00.000.
- Use Full screen for a display you can read across the room.
Tips for getting the most out of the stopwatch
- Keep the tab in front for the smoothest display — browsers throttle background tabs (the time itself stays correct).
- Mirror your screen to a TV for classroom relays so everyone can see.
- On phones, tap the Full screen button to lock the orientation and avoid accidental swipes.
- Bookmark the page — it loads instantly, and after your first visit it usually opens offline too.
Stopwatch FAQ
How accurate is this online stopwatch?
It reads your device's high-resolution performance clock. On a foreground tab it is typically accurate to a few milliseconds — like a digital wristwatch, and fine for school sports, the gym and everyday timing.
Will my time keep counting if I switch tabs?
Yes. Elapsed time is calculated from timestamps, so the total is correct when you return even if the browser paused the display.
Can I record more than one lap?
Yes, with no limit. Each lap is numbered in the list so you can scroll back through every split.
Does the stopwatch work offline?
Yes. After your first visit the browser caches the page, so it runs without signal.
Is there a keyboard shortcut to start the stopwatch?
Spacebar starts or pauses, L records a lap and R resets — whenever you are not typing in an input.
Is there a stopwatch online with laps and full screen?
Yes, this one. It is a free online stopwatch with laps that doubles as a lap timer: press Lap to record lap times and split times, and press F (or the full screen button) for a full screen stopwatch that is readable from across the room.