Ramadan & Fasting Calorie Calculator
Ramadan and other fasts compress your eating into a short window, which makes it easy to either overeat at Iftar or under-fuel and lose energy. This helps you plan calories and protein across Suhoor and Iftar so you stay energised and manage your weight.
Why people often gain weight in Ramadan
Despite fasting all day, many people gain weight, because Iftar and the evening become a feast of fried, sugary foods eaten quickly after a long fast. The fast itself doesn't cause this; the eating pattern around it does. Research on Ramadan finds weight changes are small on average and depend heavily on what and how much you eat in the window.1
How to split your calories
The calculator sets your daily calories (maintenance, or a gentle deficit if you want to lose), then divides them across Iftar and Suhoor. A larger Iftar suits most people, but a substantial, protein-rich Suhoor is what carries you through the next day's fast without crashing.
Eating for energy and muscle
- Break the fast gently: dates and water, then a balanced meal, rather than diving into fried food.
- Protein at both meals: aim for the targets above to protect muscle across a month of fasting.
- Slow carbs and fibre at Suhoor: oats, wholegrains, dairy and eggs keep you fuller and steadier through the day.
- Hydrate in the window: drink plenty between Iftar and Suhoor, and go easy on very salty and sugary foods.
Common questions
Will I lose weight during Ramadan?
It varies. Many people maintain or gain because of large evening meals; others lose. Planning your calories and leading with protein and whole foods is what decides the outcome, not the fasting alone.
Should I still exercise while fasting?
Light to moderate exercise is fine for most, often best shortly before Iftar or after it. Keep intensity sensible, stay hydrated in the eating window, and don't attempt hard training on an empty, dehydrated body.
Is it safe to cut calories while fasting?
A gentle deficit suits many healthy adults, but fasting isn't for everyone. If you're pregnant, diabetic, elderly, underweight or on medication, talk to a doctor first, this tool is general information, not medical advice.
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- Sadeghirad B, Motaghipisheh S, Kolahdooz F, Zahedi MJ, Haghdoost AA. Islamic fasting and weight loss: a systematic review and meta-analysis. Public Health Nutr. 2014;17(2):396-406. Source
- Mifflin MD, St Jeor ST, Hill LA, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241-247. Source
- Morton RW, Murphy KT, McKellar SR, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018;52(6):376-384. Source
This calculator is general information, not medical advice, and its results are estimates for healthy adults. Speak to a doctor or registered dietitian before making significant changes, especially if you are pregnant or breastfeeding, under 18, or manage a medical condition.
