Mifflin–St Jeor BMR
The equation many nutrition professionals use for adults.
Find out how many calories your body uses in a day. This calculator estimates your BMR and TDEE with the Mifflin–St Jeor equation. Fast, private, and free — no signup.
Activity: —
Harris–Benedict BMR (alternate): — kcal/day
Enter your sex, age, height, weight, and how active you are. No account needed.
The equation many nutrition professionals use for adults.
We turn your BMR into a daily calorie number based on how active you are.
An optional protein, carbs, and fat split — just a starting point, not a meal plan.
Mifflin–St Jeor (primary)
Men: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5
Women: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age − 161
TDEE = BMR × activity multiplier (1.2–1.9)
We also show revised Harris–Benedict BMR as an alternate reference. Results stay on your device; calculations run in your browser.