How the Mifflin–St Jeor equation works
For weight in kilograms, height in centimetres and age in years, the equation is:
Male equation: BMR = (10 × weight) + (6.25 × height) − (5 × age) + 5
Female equation: BMR = (10 × weight) + (6.25 × height) − (5 × age) − 161
The result is expressed as an estimated number of kilocalories per day (kcal/day). The equation provides a population-based estimate; it cannot measure an individual's metabolism directly.
BMR versus daily calorie needs
BMR estimates energy used at rest. Total daily energy expenditure also accounts for physical activity and other energy uses. Do not treat a BMR estimate as a personalized calorie target or as a recommendation to restrict food intake.
Frequently asked questions
Is BMR the same as TDEE?
No. BMR estimates energy used at rest, while total daily energy expenditure (TDEE) includes activity and other daily energy demands.
How accurate is a BMR calculator?
It is an estimate based on a formula and the values entered. Individual results can differ from measured energy expenditure.
Can teenagers use this calculator?
This page is intended for adults aged 18 and over. Growing children and teens have different nutritional considerations; use age-appropriate guidance from a qualified professional.
Should I eat exactly the number shown?
No. The result is not a meal plan or prescribed intake. Individual energy needs vary, and a qualified healthcare professional or registered dietitian can provide personalized advice.
DietDelta provides general educational information. It does not diagnose conditions or provide individualized medical nutrition therapy.
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