Find out exactly how many calories you should eat per day to lose weight safely. Science-backed formula, no signup required.
Results are estimates based on the Mifflin-St Jeor equation. Individual needs may vary.
A calorie deficit is the difference between the calories your body needs to maintain its current weight (your TDEE) and the calories you actually consume. When you eat fewer calories than you burn, your body taps into stored energy -- primarily body fat -- to make up the difference.
A deficit of roughly 500 calories per day leads to about 0.5 kg (1 lb) of fat loss per week, since 1 kg of body fat stores approximately 7,700 calories.
We use the Mifflin-St Jeor equation, the gold standard for estimating Basal Metabolic Rate (BMR). It was validated in a 2005 review by the American Dietetic Association as the most accurate BMR prediction equation.
Men: BMR = 10 x weight(kg) + 6.25 x height(cm) - 5 x age - 5
Women: BMR = 10 x weight(kg) + 6.25 x height(cm) - 5 x age - 161
TDEE = BMR x Activity Multiplier
Target = TDEE - Deficit
Most experts recommend a moderate deficit of 500 cal/day for sustainable weight loss. Deficits above 1,000 cal/day increase the risk of muscle loss, nutrient deficiencies, and metabolic adaptation. We enforce a minimum intake floor of 1,500 cal/day for men and 1,200 cal/day for women.
While the Mifflin-St Jeor equation is highly accurate for most adults, individual results may vary. Keep in mind:
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This calculator provides estimates for informational purposes only and is not a substitute for professional medical advice. Always consult a healthcare professional or registered dietitian before starting any weight loss program, especially if you have underlying health conditions.
Sources: Mifflin-St Jeor Validation (ADA 2005) | NIH Weight Management | WHO Healthy Diet