12 Hour Timer
A free 12 hour timer that opens preset to 12 hours. Press Start and it counts down in your browser, sounding an alarm at zero. Great for long focus blocks, slow cooking, study sessions and naps. No download, no signup.
What is this timer good for?
- A long focus or writing block with scheduled breaks
- Slow cooking, braising or smoking food
- Tracking a parking meter or appointment window
- A movie-length rest, nap or quiet period
- Capping screen time or a gaming session for kids
How to use it
- The timer opens preset to 12 hours.
- Adjust the hours, minutes or seconds for a different length.
- Press Start and the big display counts down.
- An alarm sounds at 00:00:00 — press Reset to run it again.
FAQ
Will it ring if I switch tabs?
Yes. The timer calibrates against your system clock, so it stays accurate even in a background tab. Just don't close the tab.
Do I need to download anything?
No. The timer runs entirely in your browser with no download, signup or plugin.
Can I change the duration?
Yes. Type any hours, minutes and seconds into the fields, or pick a related timer above.
Is it free?
Yes, it is completely free to use.