Daily Deficit Calculator
Calculate how much weight you'll lose based on your daily calorie deficit and see projected timelines.
Enter your maintenance calories (TDEE). Use the TDEE Calculator if you don't know this.
Deficits over 1000 kcal/day may cause muscle loss. 500 kcal/day is the most commonly recommended for sustainable fat loss.
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Important Disclaimer
This calculator provides estimates for educational purposes only. Results are not a substitute for professional medical or nutritional advice. Always consult a qualified healthcare provider before making significant changes to your diet or exercise routine.
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Frequently Asked Questions About Calorie Deficits
How big should my daily calorie deficit be?+
A deficit of 300–500 calories per day is a sustainable starting point for most people and leads to roughly 0.3–0.5 kg of fat loss per week. Larger deficits (up to about 750–1,000 calories) speed up weight loss but increase hunger and the risk of losing muscle.
How many calories is 1 kg of fat?+
One kilogram of body fat stores roughly 7,700 calories (about 3,500 calories per pound). So a 500-calorie daily deficit adds up to around 3,500 calories per week — approximately 0.45 kg of fat loss.
Is a 1,000 calorie deficit safe?+
For people with a lot of weight to lose, a 1,000-calorie deficit can be safe short-term, but it is too aggressive for most. It often causes fatigue, muscle loss and rebound eating. Never eat below about 1,200 calories (women) or 1,500 calories (men) without medical supervision.
Why am I not losing weight in a calorie deficit?+
Common reasons are underestimating food intake, overestimating exercise burn, water retention masking fat loss, or calorie needs dropping as you lose weight. Track intake carefully for 2–3 weeks, weigh yourself at the same time daily, and recalculate your deficit every 4–5 kg lost.