What is BMR used for?

BMR is the foundation for estimating total daily calorie needs — it's multiplied by an activity factor (see the Calorie Calculator) to estimate maintenance calories.

Why does BMR differ between men and women?

Men generally have more lean muscle mass relative to body weight, which burns more calories at rest, so the formula includes a different constant for each sex.

BMR Calculator

Calculate your Basal Metabolic Rate (BMR) — the number of calories your body burns at complete rest just to maintain basic functions.

Sex

Age

Height

Weight

Your BMR

1,699 cal/day

Calories burned at complete rest

How It Works

The Mifflin-St Jeor equation

This calculator uses the Mifflin-St Jeor equation, widely considered one of the more accurate BMR formulas: it combines your weight, height, and age, with a fixed offset that differs by sex.

BMR vs. daily calorie needs

BMR only reflects calories burned at rest — it doesn't include calories burned through daily activity or exercise. For your total daily needs, see the Calorie Calculator, which applies an activity multiplier to your BMR.

Example Calculation

A 30-year-old male who is 180cm tall and weighs 80kg has a BMR of about 1,780 calories/day.

Common Mistakes

Treating BMR as your total daily calorie needs — it doesn't include any activity, which usually adds several hundred calories or more.
Not recalculating BMR after a significant weight change, since BMR shifts with body weight.

Frequently Asked Questions

What is BMR used for?: BMR is the foundation for estimating total daily calorie needs — it's multiplied by an activity factor (see the Calorie Calculator) to estimate maintenance calories.
Why does BMR differ between men and women?: Men generally have more lean muscle mass relative to body weight, which burns more calories at rest, so the formula includes a different constant for each sex.