Which time should I enter first?
Look at the next meal on your calendar. If breakfast is the part of the day you can count on, choose My first meal. With breakfast at 8:30 AM and a 14:10 plan, the ten-hour eating window closes at 6:30 PM. You can now see whether dinner fits before you make any changes.
If dinner is already over, choose The end of my last meal. A 6:30 PM finish plus fourteen hours gives an 8:30 AM breakfast the next day. Those two entries describe the same routine from opposite ends. Use when you actually finished eating, even if that was later than you planned.
Can I fit a 12:30 lunch and a family dinner into the same window?
Suppose your first meal is during your 12:30 PM lunch break and your family finishes dinner at 8 PM. The meals span seven hours and thirty minutes. An eight-hour window that opens at 12:30 PM closes at 8:30 PM, leaving half an hour after dinner. A six-hour window closes at 6:30 PM, before dinner is over.
There’s a difference between the window you set and the interval you actually use. If you finish at 8 PM and eat lunch again at 12:30 PM tomorrow, the gap is sixteen hours and thirty minutes. To compare your own times, use the calculator for hours between meals.
How do I read a window that crosses midnight?
Put a day beside each time. If your first meal is Friday at 6 PM, an eight-hour eating window runs through Saturday at 2 AM. A sixteen-hour break from that point ends Saturday at 6 PM. The first meal and last meal fall on different dates, even though they belong to one shift.
If you eat again after work at 3 AM, record Saturday at 3 AM as the new start. For another example with a meal before work and one during a break, see the night-shift calculator.
Keep a free meal log with three entries
A note on your phone or a piece of paper is enough. Write down the day and time you finished eating, the day and time of your next meal, and the hours between them. Here is a two-night example with the same morning meal.
| Finished eating | Ate again | Interval |
|---|---|---|
| Monday 7:45 PM | Tuesday 8 AM | 12 hr 15 min |
| Tuesday 9:15 PM | Wednesday 8 AM | 10 hr 45 min |
The second dinner ended ninety minutes later. Keeping breakfast fixed shortened the interval by the same ninety minutes. If mornings are busy, this record can help you see how your evenings vary without moving breakfast. For help planning several days around the meals you want to keep, follow the first-week planning guide.
Try these examples in the free calculator