Formula
Mifflin–St Jeor estimates resting kilocalories, then an activity factor scales that result:
Male BMR = 10×kg + 6.25×cm − 5×age + 5
The female constants replace +5 with −161. Daily energy is the resting result multiplied by 1.2, 1.375, 1.55, 1.725, or 1.9. Displayed kilocalories are rounded to the nearest whole number.
Assumptions
- The equation pair is for adults, ages 18 to 100.
- Activity multipliers are planning factors, not a measured metabolism.
- A separate calorie page uses the revised Harris–Benedict equation. This page is Mifflin–St Jeor times activity.
Worked example
A 30-year-old using the male equation, at 80 kg and 180 cm, with moderate activity, has an estimated 2,759 kcal per day.
Input definitions
- Equation
- Which published constant pair to use. It is not a clinical assessment.
- Activity
- A multiplier for typical weekly movement, from sedentary to very hard work.
Limitations
This is an informational estimate for adults. It is not a diagnosis, a diet plan, or a training prescription. Pregnancy, illness, and medication can change what a safe target is.
Questions
Is this a calorie target?
No. It is an estimate of maintenance energy from a published equation. Changing intake for a goal needs personal context this page does not have.
Why are there two equations?
The 1990 Mifflin–St Jeor paper published separate constants. Choose the pair that matches the estimate you want to see.