BMR Calculator
Work out your basal metabolic rate (BMR) — the calories your body burns at complete rest — using the Mifflin-St Jeor equation.
Uses the Mifflin-St Jeor equation (1990), the current standard for estimating resting energy needs in adults. It is an estimate: real metabolic rates vary by individual, and the equation assumes typical body composition.
Frequently asked questions
What is BMR?
Basal metabolic rate is the number of calories your body would burn in a day at complete rest, just to stay alive — breathing, circulating blood, and maintaining temperature.
What is the difference between BMR and TDEE?
BMR is your resting burn. TDEE (total daily energy expenditure) is your BMR multiplied by an activity factor, giving the calories you actually burn in a normal day including movement and exercise.
Which BMR formula does this use?
The Mifflin-St Jeor equation, published in 1990 and still the most accurate general-purpose formula for adults. Older formulas such as Harris-Benedict tend to overestimate.
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