Enter your sex, age, weight, and height to estimate your basal metabolic rate, the calories you burn at rest.

Your body at rest

Basal metabolic rate is the energy your body spends just to keep you alive, breathing, circulating blood, and maintaining temperature, before any movement at all. It typically accounts for the majority of the calories you burn in a day.

This calculator uses the Mifflin-St Jeor equation, considered one of the more accurate general formulas. BMR rises with size and muscle and falls with age, which is why energy needs shift over a lifetime. To estimate your full daily need, multiply BMR by an activity factor, which the calorie calculator does for you.

The formula

Worked example

A 30-year-old man, 175 cm, 70 kg, has a BMR of about 1,649 calories per day.

How to read your result

Your BMR is the energy your body uses just to stay alive at rest. Your total daily need is higher once activity is included, which the Calorie Calculator estimates.

Frequently asked questions

What is BMR?

The number of calories your body burns at complete rest to keep basic functions running.

Why does it matter?

It is the starting point for estimating daily calorie needs.

Is the Mifflin-St Jeor equation reliable?

It is one of the most accurate general estimates, but individual metabolism varies.

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