Online Timer
A countdown timer that keeps time in a background tab.
Online Timer counts down from any duration with an audible alarm, presets for common intervals, and multiple timers side by side. It computes the remaining time from the wall clock rather than from a tick counter, so it stays accurate when the browser throttles a background tab.
Loading Online Timer…
Runs entirely on your device. No file or text you enter here is uploaded. How to verify it.
How to use Online Timer
- Set a duration, or pick a preset.
- Start it — the remaining time appears in the tab title.
- The alarm sounds when it finishes.
Questions about Online Timer
Does it keep time if I switch tabs?
Yes. Browsers throttle timers in background tabs to save battery, so a timer built on interval ticks drifts badly. This one records the target instant and computes the remainder from the clock each frame, which makes background drift impossible.
Will the alarm sound if the tab is in the background?
The sound plays, but browsers require an earlier user interaction to allow audio — starting the timer counts. A browser notification is also offered if you grant permission, which is more reliable on a phone with the screen off.
Can I run several timers?
Yes, as many as you like, each with its own label, running simultaneously.
Does it work on a phone?
Yes — it runs in any mobile browser and there is nothing to install. On iOS the tab can be suspended once you switch apps or lock the screen, so grant notification permission if you need the alert while the phone is asleep.
Is there a limit on how long a timer can run?
No fixed limit. Hours or days work as well as minutes, because the finish time is stored as a wall-clock instant rather than counted down step by step. The practical limit is the tab staying open — closing it ends the timer.
Is Online Timer really free, with no limits?
Yes. There is no account, no daily cap, no file-size tier and no watermark, because there is no server cost to recover. The site is funded by clearly disclosed partner recommendations on the Partners page, never by metering the tools.
Are my files or text uploaded when I use Online Timer?
No. Everything is processed by JavaScript running in your browser, on your device. You can verify it: open your browser's developer tools, switch to the Network tab, and use the tool. You will see no request carrying your data — because there is nowhere for it to go.