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Calculate fasting and eating windows for 16:8, 18:6, 20:4, and OMAD protocols.
Intermittent fasting is a time-restricted eating pattern that alternates between periods of fasting and eating, with the calculator determining your personalized eating window based on protocol and last meal time.
Formula
Eating Window Start = Last Meal Time + Fasting Hours | Eating Window End = Start + Eating HoursLast Meal = Time you finished your last meal
Fasting Hours = Duration of the fasting period (16, 18, 20, or 23 hours)
Eating Hours = Duration of the eating window (remaining hours in 24h)
Worked Example
16:8 protocol, last meal at 8 PM
Did you know? A 2019 study in Cell Metabolism found that time-restricted eating (a form of IF) reduced calorie intake by 20% even without conscious calorie counting, and improved cardiometabolic markers in adults with metabolic syndrome.
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