DIY Cost Tools
BMR Calculator
HEALTH CALCULATOR
Estimate an adult’s resting energy expenditure using the Mifflin–St Jeor equation.
How it works
The equation estimates resting energy expenditure from age, body mass, height, and the sex-specific constant used by the published formula.
Formula
Male: 10 × kg + 6.25 × cm − 5 × age + 5. Female: 10 × kg + 6.25 × cm − 5 × age − 161.
Worked example
For a 35-year-old male at 80 kg and 180 cm, the estimate is 1,755 kilocalories per day at rest.
Important limits
- This is a population-based estimate, not a measurement of individual metabolism.
- It is intended here for adults and does not address pregnancy, illness, athletic training, or clinical nutrition.
- Only indirect calorimetry measures resting expenditure directly.
Frequently asked questions
Is BMR the same as daily calorie need?
No. Daily needs also include movement, exercise, digestion, and other factors.
Why does the form ask for equation sex?
The published equation uses different constants for male and female study groups; it does not model every biological or clinical circumstance.
Sources and review notes
The equation comes from the original Mifflin–St Jeor study indexed by PubMed. Discuss nutrition needs with a qualified clinician or dietitian. Last reviewed September 29, 2026.