BMR Calculator
Calculate your Basal Metabolic Rate and Total Daily Energy Expenditure.
How this is calculated
Mifflin-St Jeor: BMR = 10×weight + 6.25×height − 5×age + 5 (male) or −161 (female). TDEE = BMR × activity multiplier.
Frequently Asked Questions About BMR Calculator
BMR (Basal Metabolic Rate) is the number of calories your body burns at rest just to maintain basic functions. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by your activity level, showing total daily calorie burn.
What is the difference between BMR and TDEE?
BMR is calories burned at complete rest, doing nothing. TDEE includes BMR plus calories burned through daily activities and exercise. TDEE is more useful for weight management because it shows your actual daily energy needs based on your lifestyle.
How accurate is the Mifflin-St Jeor equation?
The Mifflin-St Jeor equation is one of the most accurate modern formulas for estimating BMR, accurate within about 10-20% for most people. Actual BMR varies based on muscle mass, metabolism, and other factors. Use this as a starting estimate and adjust based on real results.
What activity level should I select?
Sedentary = little to no exercise, Lightly active = exercise 1-3 days/week, Moderately active = exercise 3-5 days/week, Very active = exercise 6-7 days/week, Extra active = intense daily exercise or physical job. Choose the level that matches your typical week.
How do I use BMR for weight loss?
To lose weight, eat fewer calories than your TDEE. A calorie deficit of 500/day typically results in 1 pound of weight loss per week. To gain weight, eat more than your TDEE. Always maintain a moderate deficit (not more than 750 calories) to preserve muscle.
Does BMR change with age?
Yes, BMR decreases with age, typically declining about 2-8% per decade after age 30. This is due to loss of muscle mass. Regular exercise and strength training help maintain BMR as you age.
Why do men and women have different BMR calculations?
Men typically have higher BMR than women because they usually have more muscle mass and less body fat. The formula accounts for this biological difference by applying different constants for males and females.