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Intermittent Fasting Calculator

Daily eating window & fasting schedule planner
Fasting Metabolic Stages:
  • 4-8 Hours: Insulin drops & glycogen depletion begins
  • 8-12 Hours: Fat burning acceleration
  • 12-16 Hours: Mild ketosis & cellular autophagy cleanup
Your Daily Schedule
Fast Breaks (First Meal)
12:00 PM (Next Day)
16 Hours Fasting Period
Eating Window: 12:00 PM – 8:00 PM (8 hrs)
Fasting Window: 8:00 PM – 12:00 PM (16 hrs)
Autophagy Begins: 8:00 AM – 12:00 PM

Frequently Asked Questions

The 16:8 method involves fasting for 16 consecutive hours every day and restricting your daily eating window to an 8-hour period (e.g. eating between 12:00 PM and 8:00 PM).

Zero-calorie beverages such as plain water, black coffee (without sugar or milk), green tea, and herbal teas are allowed and will not break your metabolic fast.

0-4 Hours: Anabolic/Digestion phase.
4-8 Hours: Blood sugar drops.
8-12 Hours: Fat burning starts.
12-16 Hours: Ketosis & Autophagy begin.