BMR Calculator - Basal Metabolic Rate Estimator

Calculate your Basal Metabolic Rate (BMR) to discover the minimum calories your body needs to function at rest. Essential for weight management and fitness goals.

BMR counts only the energy used for basic survival functions. Total calories needed depend on your physical activity level.

Discover Your Rhythm

Enter your stats to calculate your Basal Metabolic Rate using scientific models.

BMR Calculator - Basal Metabolic Rate Estimator

Calculate your Basal Metabolic Rate (BMR) to discover the minimum calories your body needs to function at rest. Essential for weight management and fitness goals. Basal Metabolic Rate (BMR) is the total number of calories your body requires to perform its most basic, life-sustaining functions. These include breathing, circulation, cell production, and nutrient processing. Essentially, if you stayed in bed all day and didn't move a muscle, your BMR is the energy your body would still consume.

Vital Functions

BMR accounts for about 60-75% of your total daily calorie expenditure, covering basic life-sustaining processes.

Aging & Metabolism

Metabolic rate typically decreases with age, often due to a reduction in lean muscle mass over time.

Mifflin-St Jeor

BMR = (10 × weight) + (6.25 × height) - (5 × age) + s

where s is +5 for males and -161 for females. Currently considered the most accurate standard.

Harris-Benedict (Revised)

Men: 88.362 + (13.397 × weight) + (4.799 × height) - (5.677 × age)

Revised by Roza and Shizgal in 1984 for better accuracy in modern populations.

Metabolic Examples

Metabolic Rate by Age

A 25-year-old male usually has a higher BMR than a 50-year-old male of the same weight, as metabolism naturally slows down with age due to loss of muscle mass.

Muscle vs. Fat Impact

An athlete with high muscle mass will have a significantly higher BMR than a sedentary person of the same weight, because muscle tissue burns more energy at rest than fat tissue.

BMR FAQ