End of fasting calculator
Enter when your fast started and how long it lasts - get the exact end time and a live countdown.
When to break your fast
The end of your fasting window is the moment your fast duration elapses from the start time. For a 16-hour fast starting at 8:00 PM, the eating window opens at 12:00 PM the next day.
Many people find it easier to break longer fasts (24+ hours) gradually: start with something light and easy to digest - fruit, broth, or yoghurt - before moving to a full meal. For standard 16:8 or 18:6 fasts, normal meals are fine.
What counts as "fast start"?
Your fast starts the moment you finish your last caloric intake - not when you decide to start fasting. If your last meal ended at 7:45 PM, that's your start time, not 8:00 PM. For precision, enter the actual time you finished eating.
Is fasting right for you?
Fasting is not suitable for everyone. If you are pregnant or breastfeeding, under 18, have diabetes or another medical condition, have had an eating disorder, or take regular medication, talk to a doctor before you fast. Mayo Clinic has an overview of intermittent fasting. This calculator only works out times; it does not give medical advice.
Track your fast in Left
Add your fast end time as a countdown in Left. Pin the widget to your Lock Screen and you'll always know exactly how long until you can eat - without mental arithmetic or checking a separate app.
Left also has a fasting timer with a Live Activity. Fasting is part of Left Premium. For a free countdown to your fast's end, see the countdown widget.
Start noticing what matters.
Download Left on your iPhone to see the time you have left, dates you are looking forward to, build the habits you want to keep, and become a better version of yourself.
Scan or search "Left" on the App Store.