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Intermittent Fasting Calculator
Calculate your eating and fasting windows based on your protocol and schedule.
Protocol Tips
16:8Most popular protocol. Skip breakfast, eat between 12:00 PM and 8:00 PM. Ideal for beginners.
18:6Slightly stricter. Eating window e.g. 1:00 PM–7:00 PM. Good for intermediates who want more fasting time.
20:4Only 4 hours of eating, e.g. 3:00 PM–7:00 PM. Requires experience and filling meals.
OMADOne meal per day. Maximum fasting time, requires a nutrient-dense, high-calorie meal.
How it works
With intermittent fasting, you alternate between eating and fasting windows. This calculator computes your personal time window based on the chosen protocol and your last or first meal time. During the fasting phase, only water, tea, and black coffee are allowed.
Read more
Intermittent Fasting Guide with Calculator →Intermittent fasting explained: protocols (16:8, 18:6, 20:4, OMAD), benefits, beginner tips, and free intermittent fasting calculator.