BMR Calculator – Basal Metabolic Rate in Calories
Calculate your basal metabolic rate (BMR)—the calories your body burns at complete rest. BMR is the foundation for weight loss planning, diet design and TDEE estimation. This calculator uses the Mifflin-St Jeor equation, recommended by dietitians and research. Enter age, gender, height and weight in metric units.
BMR Calculator
Find your basal metabolic rate—the calories your body burns at rest to maintain breathing, circulation and temperature. Uses the Mifflin-St Jeor equation, the gold standard for BMR estimation.
How the Mifflin-St Jeor BMR formula works
The Mifflin-St Jeor equation (1990) estimates resting energy expenditure:
Men: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5
Women: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age − 161
Age reduces BMR (metabolism slows with age). Height and weight increase it. The gender constant reflects differences in lean mass and hormonal factors.
BMR, weight management and diet planning
Basal metabolic rate accounts for 60–75% of total daily calorie burn in sedentary adults. The rest comes from physical activity and digestion. Athletes and very active people burn more from movement; those who sit most of the day rely more on BMR. Knowing your BMR helps you set realistic calorie targets—eating below BMR for prolonged periods is unsafe and can slow metabolism further.
For full diet planning, use the calorie calculator to combine BMR with activity level and get maintenance, mild loss, aggressive loss and gain targets. The BMI calculator complements BMR by relating weight to height. All tools run in your browser; no data is stored.