Calorie Deficit Calculator
Losing weight requires eating fewer calories than your body burns — a calorie deficit. This calculator estimates your maintenance calories using the Mifflin-St Jeor equation, then shows you daily calorie targets for different deficit levels (mild, moderate, aggressive). See your projected timeline to reach your goal weight safely.
About calorie deficits
A calorie deficit occurs when you consume fewer calories than your body burns. This calculator uses the Mifflin-St Jeor equation, which is considered one of the most accurate methods for estimating basal metabolic rate (BMR). Your Total Daily Energy Expenditure (TDEE) is then calculated by multiplying BMR by an activity factor.
A deficit of 500 calories per day results in roughly 0.5 kg (1 lb) of fat loss per week, since one kilogram of body fat stores approximately 7,700 calories. The three deficit levels shown offer different trade-offs between speed and sustainability.
Very low calorie diets (below 1,200 for women or 1,500 for men) can lead to nutritional deficiencies and should only be followed under medical supervision. This tool provides estimates for informational purposes only and is not medical advice.
Weight Loss Support
Food scales, meal prep containers, calorie tracking apps, and portion control plates.
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Frequently Asked Questions
What is a calorie deficit?
What is a safe rate of weight loss?
Should I eat back exercise calories?
What is the minimum safe calorie intake?
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