Online Stopwatch — Free, In-Browser, Millisecond Precision
A free online stopwatch that runs in your browser tab — no install, no account, no sign-up. Click Start to begin timing with millisecond precision; click Lap to record a split while the timer keeps running.
Use it for workouts, sports practice, study sprints, presentations, cooking, or any task where you need accurate elapsed time. The lap list shows both per-lap time and total elapsed time so you can review splits after the fact.
The stopwatch runs entirely on your device's clock and stays accurate for hours. Close the tab and the timer pauses; reopen the page and your laps are still there.
Laps tell the story inside the total
Total time answers 'how long did the whole thing take?'; laps answer 'what happened along the way?'. Record a lap at each kilometer, each exercise round, or each recipe step, then read the table under the display: lap time shows the length of the current segment, split time shows the running total.
One run, many reference points: coaches time split intervals, teachers pace quiz rounds, cooks time recipe stages in a single session — no separate notes to keep straight.
Accurate for seconds and for hours
The count is anchored to your device's clock rather than to screen updates, so background-tab throttling never skews it: leave the tab for an hour, come back, and the elapsed time is still exact. Running time is shown to the millisecond.
For workouts and presentations, fullscreen makes the readout readable across a room, and the Space/L/R keys cover start-pause, laps, and reset — copy the final time straight from the display or the saved lap list.
Frequently asked questions
- How do I use this online stopwatch?
- Open the page and click Start, or press Space, to count up from zero. Click Lap or press L while it is running to record a split. Click Reset or press R when paused to clear the time and all laps.
- What is the difference between a stopwatch and a timer?
- A stopwatch counts up from zero to record elapsed time and laps. A timer counts down and rings at zero. Use this stopwatch for running, training, and quizzes; use the online timer for cooking and meetings.
- How do I make the stopwatch fullscreen?
- Click the fullscreen button in the toolbar, or press F11 in your browser. The digits scale up for a classroom, gym, or second-screen display.
- What's the difference between lap time and split time?
- Both are recorded when you press Lap. Lap time is how long the current lap took (the gap since the previous lap); split time is the total elapsed time at that moment. The lap list shows both columns so you can read either depending on what you need.
- How accurate is this online stopwatch?
- The stopwatch uses your device's high-resolution timer with millisecond (1/1000s) display precision. For casual timing — workouts, study, sports drills, presentations — it's accurate to well within a frame. It's not a substitute for certified timing equipment in professional competition.
- Does the stopwatch remember my laps between visits?
- Yes. Lap entries and elapsed time are stored in your browser's localStorage. If you close the tab or refresh, the stopwatch reopens with the same elapsed time and lap list. Clear your browser data to reset.
- Is there a keyboard shortcut?
- Yes. Press Space to start or pause, L to record a lap (while running), and R to reset (while paused). The shortcuts work as long as the stopwatch tab has focus and you're not typing in an input field.
- Does it work on mobile and can I embed it?
- Yes on both. The stopwatch is mobile-friendly — main display, controls, and lap list adapt to small screens. Use the share menu to copy a link or grab an embed snippet to drop the stopwatch onto your own site.