BMR Calculator

Calculate your Basal Metabolic Rate (BMR) from your age, sex, height, and weight. Estimate the calories your body needs at rest and your approximate daily calorie needs.

Calculate your BMR

Enter your information below. This calculator uses the Mifflin–St Jeor equation to estimate BMR.

Sex

Age

Height

Height unit

Weight

Weight unit

Activity level

Please enter a valid age, height, and weight.

Your BMR

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Age	—
Height	—
Weight	—
BMR	—
Daily calorie estimate	—

Step-by-step calculation

Step 1: Convert your measurements

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Step 2: Choose the BMR equation

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Step 3: Substitute your values

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Step 4: Calculate your BMR

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Step 5: Estimate daily calorie needs

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What is BMR?

Basal Metabolic Rate (BMR) is an estimate of the number of calories your body needs to support basic functions while at rest.

These functions include breathing, circulation, maintaining body temperature, and supporting normal organ function.

BMR does not include calories burned through exercise, daily movement, digestion, or other physical activity.

How BMR is calculated

This calculator uses the Mifflin–St Jeor equation. The equation uses your sex, age, height, and weight to estimate your basal metabolic rate.

For men:
BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5

For women:
BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161

BMR example

For example, consider a 30-year-old man weighing 70 kg with a height of 175 cm.

BMR = (10 × 70) + (6.25 × 175) − (5 × 30) + 5

BMR = 700 + 1093.75 − 150 + 5

BMR ≈ 1,649 calories/day

The estimated BMR is approximately 1,649 calories per day.

BMR and daily calorie needs

BMR represents estimated energy needs at rest. Your total daily calorie needs are generally higher because they include physical activity and other energy expenditure.

Estimated daily calorie needs = BMR × Activity Factor

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Important: This calculator provides an estimate based on the information entered and the Mifflin–St Jeor equation. It is intended for general informational purposes and is not medical advice or a diagnosis.