Intermittent Fasting Schedule Calculator

Mapping out when you eat and when you fast is the practical heart of intermittent fasting, and that is exactly what this tool lays out for four common daily protocols: 16:8, 18:6, 20:4 and OMAD (One Meal A Day). Clear windows make a fasting routine easier to keep, easier to fit around work and family, and easier to sustain long enough to matter.

The logic underneath is plain arithmetic. You pick a protocol and the hour your fast starts, on a 24-hour clock, and the calculator adds the fasting hours to find when your eating window opens, then the eating hours to find when it closes. It also splits your daily calorie target across the meals that fit the window: three for 16:8 and 18:6, two for 20:4 and one for OMAD. Because it relies only on addition and subtraction against the clock, the schedule holds up across any time zone or daily rhythm.

People often forget to leave room for cooking and cleanup when they set an eating window, which turns meals into a scramble. Slashing calories far below normal on eating days is the other frequent trap, opening the door to nutrient gaps and the binge that tends to follow. Staying hydrated through the fast helps, and plain water, black coffee, or unsweetened tea all fit within the fasting window.