Calorie Deficit Calculator
Unit System
Sex
cm
kg
kg
Goal
BMR
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TDEE (maintenance)
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Daily calorie target
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Daily deficit
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Estimated time to goal
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About This Calculator
This calculator estimates your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation, then multiplies it by an activity factor to determine your Total Daily Energy Expenditure (TDEE). Based on your chosen goal and weekly rate, it calculates a daily calorie target and projects how long it will take to reach your goal weight. The projection assumes roughly 7,700 kcal per kilogram of body weight change. Results are estimates — individual metabolism, body composition, and adherence all affect real-world outcomes. Consult a healthcare professional before starting any calorie-restricted diet.
FAQ
What is TDEE?
Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a day, including your basal metabolism, physical activity, and the thermic effect of food. Eating below your TDEE causes weight loss; eating above it causes weight gain.
How is the calorie deficit calculated?
Your BMR is calculated using the Mifflin-St Jeor equation, then multiplied by an activity factor to get your TDEE. The daily deficit you select (e.g. 500 kcal/day) is subtracted from your TDEE to produce your daily calorie target.
How fast should I lose weight?
Most health organizations recommend losing 0.5–1 kg (1–2 lb) per week, which corresponds to a daily deficit of roughly 500–1,000 kcal. Losing weight faster can lead to muscle loss, nutrient deficiencies, and is harder to sustain long-term.
Is this calculator accurate?
The Mifflin-St Jeor equation is considered one of the most reliable BMR formulas for most adults. However, individual variation in metabolism, body composition, and non-exercise activity means actual calorie needs may differ by 10–15%. Treat the results as a starting point and adjust based on real-world progress.