Does the stopwatch keep running if I switch tabs?

Yes. The timer uses JavaScript’s Date.now() for timing rather than counting intervals, so it stays accurate even when the tab is in the background. The current time is shown in the browser tab title so you can monitor it from other tabs.

How accurate is the online stopwatch?

This stopwatch uses Date.now() / requestAnimationFrame for high-resolution timing, accurate to the millisecond. Browser tab throttling may affect very precise measurements when the tab is in the background, but elapsed time stays correct.

Can I use the timer without sound?

Yes. The audio alert is optional. If you prefer a silent timer, you can rely on the visual flash when the countdown ends. Browser notification support is requested separately.

What is an interval timer?

An interval timer alternates between work and rest periods for a set number of rounds. It is used for HIIT workouts, Tabata training, circuit training, boxing rounds, and any exercise format with structured work-rest intervals.

Can I export my lap times?

Yes. Click the Export CSV button in the stopwatch mode to download all lap times as a spreadsheet-compatible CSV file.

Free Online Stopwatch & Timer

A precise stopwatch with laps and CSV export, a countdown timer with audio and notifications, and an interval timer for HIIT — all running in your browser tab title so you can watch from anywhere.

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Shortcuts: Space start/pause · L lap · R reset

Lap	Lap time	Total time

Frequently Asked Questions

Does the stopwatch keep running if I switch tabs?: Yes. The timer uses JavaScript’s Date.now() for timing rather than counting intervals, so it stays accurate even when the tab is in the background. The current time is shown in the browser tab title so you can monitor it from other tabs.
How accurate is the online stopwatch?: This stopwatch uses Date.now() / requestAnimationFrame for high-resolution timing, accurate to the millisecond. Browser tab throttling may affect very precise measurements when the tab is in the background, but elapsed time stays correct.
Can I use the timer without sound?: Yes. The audio alert is optional. If you prefer a silent timer, you can rely on the visual flash when the countdown ends. Browser notification support is requested separately.
What is an interval timer?: An interval timer alternates between work and rest periods for a set number of rounds. It is used for HIIT workouts, Tabata training, circuit training, boxing rounds, and any exercise format with structured work-rest intervals.
Can I export my lap times?: Yes. Click the Export CSV button in the stopwatch mode to download all lap times as a spreadsheet-compatible CSV file.