Calorie Calculator
Estimate how many calories your body burns each day — and what to eat to maintain, lose or gain weight — using the Mifflin-St Jeor equation, the formula most US dietitians consider the gold standard.
Your Basal Metabolic Rate (BMR) is the energy your body burns at complete rest — breathing, circulation, cell repair. Mifflin-St Jeor estimates it from weight, height, age and sex, and studies show it is typically within 10% of measured values.
Total Daily Energy Expenditure (TDEE) multiplies BMR by an activity factor, from 1.2 for a sedentary lifestyle to 1.9 for athletes and physical workers. Eating at your TDEE maintains weight; a deficit of about 500 calories per day loses roughly one pound per week, since a pound of body fat stores about 3,500 calories.
Worked examples
Moderately active man
A 32-year-old man, 5′10″, 170 lb, exercising 3–5 days a week: BMR ≈ 1,670, TDEE ≈ 2,590.
→ ≈ 2,590 cal to maintain
Weight loss target
Eating 500 calories below TDEE loses about 1 lb per week — a sustainable pace for most people.
→ TDEE − 500 cal
Sedentary woman
A 45-year-old woman, 5′4″, 150 lb, desk job: BMR ≈ 1,320, TDEE ≈ 1,585.
→ ≈ 1,585 cal to maintain