About the intermittent fasting timer
Start the timer when you finish your last meal. The screen shows the exact day and time your fast ends, and because the countdown is saved in your browser you can close the tab and check back any time.
This is a timing tool, not medical advice. Talk to a doctor before fasting if you are pregnant, diabetic, take medication or have a history of eating disorders.
Recommended times
| 12:12 | 12 hours |
|---|---|
| 14:10 | 14 hours |
| 16:8 | 16 hours |
| 18:6 | 18 hours |
| 20:4 | 20 hours |
| 24 h | 24 hours |
How to use the intermittent fasting timer
- Choose a preset, or tap Edit time to type any hours, minutes and seconds.
- Press Start Timer (or the space bar). The finish time appears under the digits.
- Press Full screen to fill the screen — handy for classrooms, meetings and kitchens.
- When it reaches zero an alarm plays until you press Stop Alarm.
Keyboard shortcuts
- Space start / pause
- R reset
- F full screen
- M mute
Frequently asked questions
What does 16:8 fasting mean?
16 hours of fasting followed by an 8-hour eating window. For example, finish dinner at 8 pm and eat again at noon the next day.
Will the fasting timer keep running if I close my browser?
Yes. The end time is stored on this device. Reopen the page in the same browser and it shows the time remaining. The alarm can only sound while the page is open.
Can I start the timer for a fast that already began?
Yes. Tap Edit time and enter how long is left, e.g. 13 h 20 m, then press Start.
What presets does the intermittent fasting timer have?
12:12 (12 hours), 14:10 (14 hours), 16:8 (16 hours), 18:6 (18 hours), 20:4 (20 hours), 24 h (24 hours). Tap Edit time to set any other length.
Is it free, and do I need an app?
It is completely free with no sign-up or download. It works in any modern browser on phones, tablets and computers.