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BMR Calculator

Your Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest. Enter your details to estimate your BMR and daily maintenance calories.

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Enter your details and tap Calculate to see your BMR and daily calorie needs.
This tool provides general informational estimates only and is not medical advice, diagnosis, or treatment. Results use population-average formulas and may not fit your individual situation. Always consult a qualified healthcare professional before making health, diet, or medical decisions.

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What is BMR?

Your Basal Metabolic Rate is the energy your body uses to keep you alive at rest — breathing, circulating blood, regulating temperature and basic cell function. It typically accounts for 60–70% of the calories you burn each day.

How is it calculated?

This calculator uses the Mifflin–St Jeor equation, considered the most accurate predictive formula for most healthy adults:

Your maintenance calories multiply BMR by an activity factor (1.2 sedentary up to 1.9 extra active).

Frequently asked questions

What is the difference between BMR and maintenance calories?

BMR is what you burn at complete rest. Maintenance calories (sometimes called TDEE) add the energy you burn through daily movement and exercise, so they are always higher than BMR.

Which formula does this BMR calculator use?

It uses the Mifflin–St Jeor equation, which research has shown to be more accurate than the older Harris–Benedict equation for most people.

Is BMR the number of calories I should eat?

No. Eating only your BMR is usually too low. Use your maintenance calories as a baseline and adjust for your goal — and consult a professional for a personalized plan.

Sources & methodology

Formulas and reference ranges used by this calculator come from peer-reviewed and official public-health sources:

  1. Mifflin MD, St Jeor ST, et al. "A new predictive equation for resting energy expenditure in healthy individuals." American Journal of Clinical Nutrition, 1990. (Mifflin–St Jeor equation — the current standard recommended by the Academy of Nutrition and Dietetics.)
  2. Activity multipliers based on the Harris–Benedict physical activity levels (sedentary to extra active).
  3. U.S. National Institutes of Health — dietary energy and nutrition guidance: nih.gov.
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