12 Hour Timer

Twelve hours, running long.

12:00:00

12 Hour Timer ready. Press start to begin.

Each mark is 15 minutes

Twelve hours is half a day — a long shift, an overnight prove, or the gap between doses. At this length you want the reminder somewhere more durable than a browser tab.

What 12 hours is good for

An overnight wait

A ferment, a soak, or a charge that finishes while you are asleep.

A long shift

Half a day with a visible end.

Questions

Will it survive the tab being closed?

No. The countdown lives in the page, so closing the tab ends it. For twelve hours, use a phone alarm — this page is better as a visible marker than as the thing you rely on.

Will it make a sound when it finishes?

Yes — an alarm rings when the countdown reaches zero. The countdown also turns red and the tab title changes to "Time's up", so the end is visible as well as audible.

The hard part isn’t the timer

This page counts down, and that is all it does. Porotimer handles the part that decides whether the session actually works.

  • Porotimer's allow list, with Study Focus selected

    Lock away what breaks focus

    Choose the apps you're allowed for the session. Porotimer puts everything else behind a wall until the timer ends — which is the one thing a page in a browser tab can never do.

    Learn more
  • Porotimer's guided break screen

    Breaks that actually rest you

    A calm scene and a breathing guide when the sprint ends, instead of five minutes of scrolling. You come back settled rather than scattered.

    Learn more
  • Porotimer's session path for the day

    See where the hours went

    Every sprint and break laid out in order. The day becomes something you can look back on, rather than something you try to remember.

    Learn more

Start the next one in the app

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