Does the timer alarm work if I switch tabs?

The countdown keeps running in the background and the alarm sounds when it reaches zero, as long as the tab isn't fully discarded by the browser. For long timers, keep the tab open; some browsers throttle background tabs, which can delay the sound slightly.

Online Stopwatch & Timer

A precise stopwatch with laps and a countdown timer with an alarm, in one place. Works offline once loaded, and you can install it as an app.

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Stopwatch & timer, explained

The stopwatch counts up with hundredth-of-a-second precision and records lap splits — handy for workouts, cooking steps or timing anything repeatable. The timer counts down from any duration (or a quick preset like the 25-minute Pomodoro) and sounds an alarm at zero.

Works offline & installable

Because the whole tool runs in your browser, it keeps working without internet after the first load, and you can add it to your home screen or desktop as an app from your browser's menu.

Private by design. No accounts, no tracking of your timers — it all runs locally.

Frequently asked questions

Does the alarm work if I switch tabs?

The countdown keeps running and sounds at zero as long as the tab stays open; some browsers throttle background tabs, which can delay it slightly.

How accurate is the stopwatch?

It uses the browser's high-resolution timer and shows hundredths of a second — accurate for everyday use.

Does it work offline?

Yes — it's cached after your first visit and even installable as an app.

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