Online Stopwatch
Free online stopwatch with millisecond precision, lap times and keyboard shortcuts. Start, pause and reset instantly - runs entirely in your browser, nothing to install.
How accurate is this online stopwatch?
The stopwatch uses your browser's high-resolution performance clock, giving millisecond-level accuracy. Actual precision depends on your device, but for sports, study sessions and everyday timing it is more than accurate enough.
Is the stopwatch free to use?
Yes, the stopwatch is completely free with no limits, sign-up or ads blocking the timer. You can run it as long as you like in any modern browser.
What is a lap time and how do I record one?
A lap time is the duration of a single segment of your activity. While the stopwatch is running, press the Lap button (or the L key) to record the current lap; each lap's time and the running total are listed in the table.
What do the green and red lap times mean?
The green lap time marks your fastest lap and the red one marks your slowest lap, so you can instantly compare segments of a workout, race or task without doing any math.
Does the stopwatch keep running if I switch browser tabs?
Yes. The elapsed time is calculated from your device's internal clock rather than the visible animation, so switching tabs or briefly losing focus will not lose any time.
Can I use keyboard shortcuts with the stopwatch?
Yes. Press Space to start or pause, L to record a lap and R to reset. This makes it easy to operate the stopwatch without taking your eyes off your activity.
Does the stopwatch work offline?
Once the page has loaded, all timing is computed locally on your device. No internet connection is needed during measurement and no data is ever sent to a server.
What can I use an online stopwatch for?
Common uses include interval training and running laps, cooking and baking timers, study or work sprints, board games, presentations and any task where you want to measure how long something takes.
How to Use Online Stopwatch
A precise online stopwatch with millisecond accuracy, lap timing and keyboard control. Everything runs locally in your browser — no sign-up, no data leaves your device.
- Press the green Start button (or hit Space) to begin timing; the large display updates in real time down to hundredths of a second.
- While the stopwatch is running, press Lap (or the L key) each time you complete a segment — every lap time and the running total appear in the table below, newest first.
- Look for the green and red highlighted rows: green marks your fastest lap, red your slowest, so you can compare segments at a glance.
- Press Pause (or Space) to stop timing without clearing anything, and Resume to continue from where you left off.
- Press Reset (or the R key) to clear the timer and all lap records and start a fresh measurement.
Keep the tab in the background while timing — the clock is based on your device's internal time, so the count stays accurate even when the page is not visible.
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