Your BMR (Basal Metabolic Rate) is the number of calories your body burns at rest to maintain basic functions like breathing and circulation. It’s calculated using your weight, height, age, and gender via the Mifflin-St Jeor equation.
BMR Calculator
BMR Formula (Mifflin-St Jeor Equation)
Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age(years) + 5
Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age(years) − 161
Example: A 30-year-old man weighing 70 kg at 175 cm has a BMR of (10 × 70) + (6.25 × 175) − (5 × 30) + 5 = 1,673 calories/day.
How to Use the BMR Calculator
- Select your gender.
- Enter your age in years.
- Enter your weight in kilograms and height in centimeters.
- Click “Calculate BMR” to see your result instantly.
Frequently Asked Questions
What is BMR used for?
BMR tells you the minimum calories your body needs at rest. It’s the starting point for calculating your total daily energy expenditure (TDEE) once activity level is factored in.
Why does BMR differ by gender?
Men generally have more lean muscle mass than women at the same weight, which burns more calories at rest, so the formula subtracts a smaller amount for men.
Is BMR the same as the calories I should eat?
No. BMR only reflects resting calorie burn. To find your total daily calorie needs, multiply BMR by an activity factor, which a TDEE calculator accounts for.
Does BMR decrease with age?
Yes, BMR typically declines with age due to gradual loss of muscle mass, which is why the formula subtracts more calories per year of age.