Estimate adult basal metabolic rate with Mifflin–St Jeor or revised Harris–Benedict, using metric or US customary measurements.
Basal metabolic rate describes energy use under strict resting conditions. These predictive equations estimate daily resting energy expenditure from adult population data; their outputs are labeled BMR estimates here, but a measured BMR and resting metabolic rate are not interchangeable tests. Total daily energy expenditure adds activity assumptions.
Body composition, health, age, and measurement conditions can make an individual result differ from laboratory testing.
Male: 10W + 6.25H − 5A + 5 · Female: 10W + 6.25H − 5A − 161Male: 88.362 + 13.397W + 4.799H − 5.677A · Female: 447.593 + 9.247W + 3.098H − 4.330AFor a 30-year-old male weighing 70 kg and measuring 175 cm, Mifflin–St Jeor estimates 10×70 + 6.25×175 − 5×30 + 5 = 1,648.75 kcal/day.
BMR estimates resting energy. TDEE multiplies BMR by an activity assumption and is intended to approximate full-day expenditure.
US customary measurements are converted to kilograms and centimeters before either equation is evaluated.
Basal metabolic rate is an estimate of the energy your body uses over 24 hours to support basic functions while at rest.
This calculator applies either the Mifflin–St Jeor or revised Harris–Benedict equation to age, height, weight, and the sex term specified by the selected formula.
Mifflin–St Jeor is commonly used as a modern default, but neither equation is exact for every person. Direct measurement is needed for an individualized value.
BMR estimates energy use at rest. Total daily energy expenditure, or TDEE, also includes movement, exercise, and the energy used to digest food.
BMR can be one starting point for estimating daily needs, but it is not itself a calorie target and must be adjusted for activity and individual circumstances.
These historical population equations include male and female constants because those variables improved their statistical estimates. They cannot capture each person’s body composition or physiology.
They are related estimates but use different testing conditions. Resting metabolic rate is generally measured under less restrictive conditions and may be slightly higher.
No. This calculator is intended for adults ages 18 to 120. Children need age-appropriate assessment from a qualified professional.
Equation results are estimates. Pregnancy, breastfeeding, illness, medications, body composition, and other individual factors can change actual energy use.