Free meal-time tools
Fasting Start Time Calculator
Choose when you want to eat again and work backward to find the last meal time for your planned fasting interval.
When should I start my fast?
Finish your last meal by
Worked example
If Saturday brunch is at 11:30 am and you plan a 14-hour interval, finish eating by 9:30 pm on Friday. If brunch moves an hour later, your Friday finish time also moves an hour later.
Enter the time of the meal you want to keep, then change the interval to compare schedules. The previous-day label refers to the calendar day before that meal. These are clock-time examples assuming no time-zone or daylight-saving change.