Online timer

Set a countdown, get an alarm. Accurate even in a background tab.

05:00

How this works

  • It keeps time from the clock, not from ticks — browsers slow a background tab down to one update a second and stop it altogether on a sleeping phone. Counting frames would drift badly; this works out the remaining time from when you pressed Start, so it is right whenever you look at it.
  • The tab title shows the countdown — so you can leave it in a background tab and still see how long is left without switching to it.
  • The alarm needs one click first — browsers only allow sound after you interact with the page, so pressing Start is what lets the alarm play later. If you never press it, nothing will sound.
  • Nothing is recorded — no account, no history, nothing sent anywhere. Reloading the page starts over.

Pick a duration and press start. The remaining time is big enough to read across a room, the alarm sounds when it reaches zero, and the countdown appears in the tab title so you can leave it in a background tab and still see how long is left.

The part that is easy to get wrong is accuracy. A browser slows a background tab down to one update a second, and stops updating it altogether on a sleeping phone — so a timer that counts its own ticks drifts, sometimes by minutes. This one works out the remaining time from the moment you pressed start, so it is right whenever you look at it, however long the tab spent hidden.

Nothing is stored and there is no account. Close the tab and it is gone.

How to use it

  1. Pick a duration, or type hours, minutes and seconds.
  2. Press start.
  3. Leave the tab in the background if you like — the title shows the countdown.
  4. The alarm sounds at zero.

Frequently asked questions

Will it still work if I switch tabs or lock my phone?

The countdown stays accurate, because it is calculated from the clock rather than from counted ticks. The alarm, though, needs the page to be alive: a phone that has fully suspended the tab may not play it until you return. For anything you must not miss, use your phone’s own alarm.

Why is there no sound?

Browsers only allow audio after you interact with the page, so pressing Start is what unlocks it. If sound is switched off, or the tab was suspended, the timer finishes silently. The display and the tab title still change.

Can I run several timers at once?

Open the page in more than one tab. Each keeps its own countdown, and each tab title shows its own.

Is anything saved?

No. There is no account and nothing is stored or sent. Reloading the page starts over.

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