How to Use This Calculator
Enter weight, height, age, sex, and your preferred formula. The calculator returns your BMR — the minimum calories your body burns daily at complete rest — plus weekly and hourly equivalents. Multiply by your activity factor to get your TDEE.
Formula & Background
Mifflin-St Jeor (recommended for most adults):
Male: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
Female: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
Harris-Benedict (classic formula):
Male: BMR = 88.362 + 13.397 × weight + 4.799 × height − 5.677 × age
Male: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
Female: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
Harris-Benedict (classic formula):
Male: BMR = 88.362 + 13.397 × weight + 4.799 × height − 5.677 × age
Calculation Example
Male, 30 years, 175 cm, 75 kg (Mifflin-St Jeor):
BMR = 10×75 + 6.25×175 − 5×30 + 5 = 750 + 1,093.75 − 150 + 5 = 1,699 kcal/day
Expert Tips
- BMR is your floor, not your calorie target. Multiply by an activity multiplier (1.2–1.9) to get TDEE.
- Moderately active (3–5 workouts/week): TDEE ≈ BMR × 1.55
- Never eat below BMR for extended periods — chronic undereating suppresses thyroid function and metabolic rate.
- Mifflin-St Jeor is more accurate for most adults; Harris-Benedict tends to overestimate by 5–8%.
- BMR naturally declines ~2–3% per decade as lean muscle mass decreases with age.