BMR Calculator

Estimate the number of calories your body uses at rest each day with the Mifflin-St Jeor equation.

Calculator

Estimate basal metabolic rate using the Mifflin-St Jeor equation.

Choose units

What Is BMR?

Basal Metabolic Rate (BMR) is an estimate of the energy your body uses to maintain basic functions such as breathing, circulation and cell activity while at rest.

Formula Used

This calculator uses the Mifflin-St Jeor equation, which estimates resting energy expenditure from weight, height, age and sex.

How to Use the BMR Calculator

  1. Select your unit system.
  2. Enter sex, age, height and weight.
  3. Select Calculate to see the estimated calories used at rest per day.

BMR vs TDEE

BMR estimates energy needs at rest. TDEE adds an activity factor to estimate total daily energy expenditure. For planning calorie intake, TDEE is usually the more practical next step.

Limitations

BMR equations provide population-based estimates. Individual energy expenditure can vary because of body composition, genetics, health status, environment and other factors.

Related Calculators

Frequently Asked Questions

Does BMR include exercise?

No. BMR represents energy use at rest. Activity is accounted for when estimating TDEE.

Can BMR change over time?

Yes. Changes in age, weight and body composition can change estimated BMR.

Should I eat exactly my BMR calories?

BMR is not a recommended calorie intake. Daily needs are better estimated using total energy expenditure and individual goals.

Methodology & References

Mifflin-St Jeor: 10×weight(kg) + 6.25×height(cm) − 5×age + sex constant (+5 male, −161 female).

Important: These results are estimates for general informational and educational purposes. They are not a diagnosis and do not replace individualized advice from a qualified healthcare professional.