Basal metabolic rate is the number of calories your body burns at complete rest just to stay alive — breathing, circulation, cell repair, and brain function. It typically accounts for 60%-70% of your total daily calorie burn.

How is BMR different from TDEE?

BMR is calories at rest; TDEE (total daily energy expenditure) multiplies BMR by an activity factor to include movement and exercise. TDEE is the number to use for weight management.

BMR Calculator

Q: What is the Mifflin-St Jeor formula?

For men: BMR = 10×kg + 6.25×cm − 5×age + 5. For women: 10×kg + 6.25×cm − 5×age − 161. It is the equation most dietitians consider the most accurate for the general population.

Find your basal metabolic rate — the calories your body burns at complete rest — using the Mifflin-St Jeor equation dietitians trust most.

Your BMR

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calories per day at complete rest

Sedentary (×1.2)

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Lightly active (×1.375)

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Moderately active (×1.55)

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Very active (×1.725)

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The Mifflin-St Jeor equation

Men: BMR = 10×kg + 6.25×cm − 5×age + 5
Women: BMR = 10×kg + 6.25×cm − 5×age − 161

Worked example

Man, 30, 178 cm, 75 kg:

10×75 + 6.25×178 − 5×30 + 5 = 750 + 1,112.5 − 150 + 5 = ~1,718 calories/day at rest.

What BMR is (and how to use it)

Your BMR is the biggest single piece of your daily calorie burn — the energy to keep your heart beating, lungs working, and cells repairing while you do nothing. It rises with muscle mass and body size, and falls gradually with age. On its own, BMR isn't the number to eat to; multiply it by an activity factor to get your TDEE (maintenance calories), then set a target with the calorie calculator. The activity-adjusted rows above are a shortcut to that TDEE estimate.

Frequently asked questions

What is BMR?

Calories burned at complete rest — 60–70% of your total daily burn.

What is the Mifflin-St Jeor formula?

Men: 10×kg + 6.25×cm − 5×age + 5. Women: same but − 161.

BMR vs. TDEE?

BMR is at rest; TDEE multiplies it by activity to give maintenance calories.

Related calculators

Medical disclaimer: BMR is an estimate for healthy adults and varies with body composition and genetics. Not medical advice. Consult a healthcare provider or dietitian for personalized guidance. Formula: Mifflin-St Jeor (1990). Last reviewed: July 2026.