BMR Calculator (Basal Metabolic Rate)

BMR by Mifflin-St Jeor: 10×weight(kg) + 6.25×height(cm) − 5×age, then +5 for males or −161 for females — a 70 kg, 175 cm, 30-year-old male burns about 1649 kcal/day at rest.

Informational only — not medical advice. Consult a qualified professional for personal health decisions.

Your basal metabolic rate is the energy your body uses at complete rest — breathing, circulation, cell repair. This calculator uses the Mifflin-St Jeor equation, the estimate most dietetics research recommends for healthy adults. For total daily calories including activity, continue to our calorie calculator.

Formula & methodology

Mifflin-St Jeor (metric): BMR = 10w + 6.25h − 5a + s where w = weight kg, h = height cm, a = age years, s = +5 (male) or −161 (female).

Worked examples

Male, 70 kg, 175 cm, 30 y → 700 + 1093.75 − 150 + 5 = 1648.75 kcal/day
Female, 60 kg, 165 cm, 25 y → 600 + 1031.25 − 125 − 161 = 1345.25 kcal/day

Limits

The equation targets healthy adults 18+; it does not account for unusual muscle mass, pregnancy, or medical conditions affecting metabolism. BMR is not your daily calorie need — multiply by an activity factor (see the calorie calculator) for that.

Frequently asked questions

What is the difference between BMR and TDEE?

BMR is energy burned at complete rest; TDEE multiplies BMR by an activity factor to estimate your full daily burn. Our calorie calculator computes TDEE.

Why Mifflin-St Jeor rather than Harris-Benedict?

Validation studies found Mifflin-St Jeor predicts measured resting energy expenditure more accurately for most modern adults, so it is the default in dietetics practice.