Estimate resting energy needs with the Mifflin–St Jeor equation using age, height, weight, and the selected sex variable.
Your Basal Metabolic Rate
Calories/day consumed at complete rest.
How Basal Metabolic Rate Is Estimated
This calculator uses the Mifflin–St Jeor equation. It combines body weight in kilograms, height in centimetres, and age, then applies the equation's sex-specific adjustment to estimate resting energy expenditure in calories per day. Unit conversions are made before the estimate is calculated.
BMR is not total daily energy use
BMR represents an estimate of energy used at rest. It does not include all movement, exercise, digestion, or day-to-day activity. A daily calorie target would require additional assumptions and may differ from a measured metabolic rate.
Health note: This is a general estimate, not a dietary prescription or medical assessment. Individual needs vary with health, medication, pregnancy, age, and other factors.
Source and important context
The Mifflin–St Jeor equation was published as a predictive equation for resting energy expenditure in healthy adults. Individual measured energy needs can differ from an equation-based estimate. PubMed: Mifflin–St Jeor equation. This page provides general educational estimates and is not a diagnosis or a substitute for individualized care. Page information updated: 4 November 2026.
Example and limitations
Resting energy expenditure is not the same as total daily energy expenditure. Movement, exercise, food digestion, health status, and individual variation affect total daily needs.