BMR Calculator

Understanding Basal Metabolic Rate (BMR)

Your Basal Metabolic Rate (BMR) represents the number of calories your body needs to maintain basic life-sustaining functions—such as breathing, circulation, cell production, and temperature regulation—while at complete rest.

Mifflin-St Jeor Equation

Introduced in 1990, this is the modern standard for calculating BMR:

• **Men:** $\text{BMR} = 10 \times \text{weight (kg)} + 6.25 \times \text{height (cm)} - 5 \times \text{age (years)} + 5$
• **Women:** $\text{BMR} = 10 \times \text{weight (kg)} + 6.25 \times \text{height (cm)} - 5 \times \text{age (years)} - 161$

Revised Harris-Benedict Equation

Originally published in 1918 and revised in 1984 by Roza and Shizgal, this remains a widely compared historic standard:

• **Men:** $\text{BMR} = 13.397 \times \text{weight (kg)} + 4.799 \times \text{height (cm)} - 5.677 \times \text{age (years)} + 88.362$
• **Women:** $\text{BMR} = 9.247 \times \text{weight (kg)} + 3.098 \times \text{height (cm)} - 4.330 \times \text{age (years)} + 447.593$