🕌 Ramadan Mode
Ramadan Fasting Calculator
Calculate your Ramadan fasting window from Suhoor (pre-dawn) to Iftar (sunset). Ramadan typically involves 13–18 hours of fasting depending on location and time of year.
Step 1 — Choose Your Protocol
16:8 is the most popular protocol — fast 16h, eat within 8h.
Step 2 — Personalise Your Schedule
Your eating window starts from this time
🎯 Your Goal
⏱ Time Checkpoints
Your Fasting Timeline
Elapsed-time checkpoints for a 16-hour schedule. These do not measure metabolic changes.
Fast Started
+0hThe clock measures time since your last calories. It does not measure digestion or metabolic changes.
📄 Mayo ClinicEarly Fasting
+2hDigestion and nutrient absorption vary with the meal and the individual.
📄 NIH — Metabolism OverviewBetween Meals
+4hYour body uses a mixture of fuels. Time alone cannot identify your blood glucose or insulin level.
📄 PubMed — Insulin & Glucose DynamicsOvernight Interval
+8hAn overnight interval may include sleep. Glycogen use varies with diet and activity.
📄 Cahill GF Jr — NEJM 197012 Hours Elapsed
+12hTwelve hours is a time checkpoint, not a diagnosis of ketosis. Ketone production varies between people.
📄 Cahill GF Jr — NEJM 197016 Hours Elapsed
+16hSixteen hours does not establish autophagy activation. There is no validated universal human autophagy timer.
📄 Levine & Kroemer — Cell 2008Time checkpoints are educational, not a recommendation to extend your fast.
🕌 Using This Calculator for Ramadan
Set Your Eating Start = Iftar Time
Enter your local Iftar (sunset) time as the “eating start time”. The calculator will show your eating window from Iftar onward.
Typical Ramadan Fasting Duration
Depending on your location and the time of year, Ramadan fasting typically lasts 13–18 hours — this duration does not confirm ketosis or autophagy.
Nutrition During Ramadan
Focus on complex carbohydrates, lean protein, and healthy fats at Suhoor for sustained energy. At Iftar, break your fast gently with dates and water before your main meal.
Medical Disclaimer
This tool provides estimates for informational purposes only. Always consult a licensed healthcare provider before beginning any fasting protocol — especially if you are pregnant, have a history of eating disorders, diabetes, or any other medical condition.
Sources: Mayo Clinic · NIH · PubMed