How to Use the Fasting Timer

Pick a protocol, start the timer, watch your progress.

The Fasting Timer runs six intermittent-fasting protocols with a live countdown and a timeline of what's happening in your body at each stage of the fast.

Step by step

1
Choose a protocol
Pick from six protocols: 12:12 (Beginner), 16:8 (Beginner), 18:6 (Intermediate), 5:2 (Intermediate), 20:4 / Warrior (Advanced), or OMAD (Advanced) — the numbers are hours fasting : hours eating.
2
Start the fast
Tap Start Fast. A live timer begins counting toward your protocol's fasting-hour target.
3
Follow the body timeline
As the fast progresses, the screen shows what's typically happening physiologically at your current hour — from active digestion early on through later fasting stages.
4
End the fast
Tap End Fast whenever you're done, whether or not you reached the full target. It's logged either way.
5
Check your history and streak
Past fasts are listed with their duration and how much of the target you completed, along with your total fasts, total hours, average completion, and current streak.

Your fasting history lives in your browser, not your account

This is the one thing worth knowing before you rely on it: fasting state and history are saved to this browser's local storage, not synced to your MyCookingCalendar account. Switching devices, using a different browser, or clearing your browser's site data will lose your fasting history and streak. History keeps your most recent 30 fasts.

Tips

If you're new to fasting, 12:12 or 16:8 are the two protocols marked Beginner.
Ending a fast early still logs it — your completion percentage just reflects that it was cut short.

Frequently asked questions

Will my fasting history show up if I open the app on another device?

No. Fasting history and your current streak are stored locally in this browser, not on the server, so they don't sync across devices.

What happens if I clear my browser data?

Your fasting history, streak and any fast in progress will be lost — there's no server-side backup for this tool.

What's the difference between the protocols?

The number pair is hours fasting : hours eating — e.g. 16:8 means a 16-hour fast with an 8-hour eating window. 5:2 is different: it's normal eating 5 days a week with calorie restriction on 2 non-consecutive days rather than a daily eating window.

Want the bigger picture first? See what Fasting Timer does →

Ready to try it?

Open the tool