BMR Calculator (Mifflin-St Jeor)

Your basal metabolic rate is the energy your body uses at complete rest — breathing, circulating blood, keeping warm. This calculator uses the Mifflin-St Jeor equation, the one most dietitians start from today.

This equation is for adults (18+). Children's and teenagers' energy needs are worked out differently — ask us.

Basal metabolic rate

kcal/day

Enter your age, height and weight

About kcal an hour, at complete rest

Mifflin-St Jeor (1990)

This is what your body burns at rest — not what you should eat. Your daily needs include activity: see the TDEE Calculator.

Your results are attached to the form below

These figures are estimates for general awareness only and are not medical advice or a diagnosis. Read our Medical Disclaimer.

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How this is calculated

Mifflin-St Jeor (Mifflin et al., American Journal of Clinical Nutrition, 1990): women BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161; men the same but + 5 instead of − 161. The published coefficients (9.99 and 4.92) are conventionally rounded to 10 and 5.

Why Mifflin-St Jeor?

A 2005 systematic review for the American Dietetic Association compared the four equations most used in practice — Harris-Benedict, Mifflin-St Jeor, Owen and WHO/FAO/UNU. Mifflin-St Jeor predicted resting metabolism within 10% of the measured value in more people, both normal-weight and obese, than any of the others.

Its limits

The same review noted that older adults and ethnic minorities were under-represented in the studies, and ICMR-NIN has found that international equations tend to overestimate Indians' resting metabolism. Treat the result as an estimate: the BEE Calculator shows ICMR-NIN's own adjustment for Indian adults.

Other BMR methods

See the Harris-Benedict Calculator for the classic equation, the Katch-McArdle Calculator if you know your body fat, or the RMR Calculator for resting metabolic rate. To turn BMR into daily calories, use the TDEE Calculator.