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Mifflin-St Jeor BMR Calculator

BMR with the Mifflin-St Jeor equation, the most accurate general-purpose formula.

Quick answer: Mifflin-St Jeor: men 10 × kg + 6.25 × cm − 5 × age + 5; women the same minus 161. It is generally the most accurate BMR equation for the general population and the default in most clinical guidance.

cm
kg
years
BMR
1,669 kcal
Activity
Moderately active
BMR (at rest)1,669 kcal/day

BMR across formulas

FormulaBMR (kcal/day)
Mifflin-St Jeor (1990)1,669
Harris-Benedict revised (1984)1,722
Katch-McArdle (lean mass)1,583

BMR is what your body burns at complete rest; TDEE adds daily activity and exercise. These are estimates based on population formulas and can be 10–15% off for any individual — track your weight over 2–3 weeks and adjust intake from the real trend. Not medical advice.

Core facts
Published1990
AccuracyBest general-purpose BMR formula
Men+5 constant
Women−161 constant

What is Mifflin-St Jeor Calculator?

The Mifflin-St Jeor equation, published in 1990, was developed to improve on the older Harris-Benedict formula and has repeatedly been shown to be more accurate for the general population. It uses weight, height, age and sex, with a fixed offset that differs for men and women. Because it needs no body fat measurement it is practical for almost anyone, and it is the default in most dietetic practice. Its main limitation is that it treats all body weight alike, so it is less accurate for very muscular or very obese people — where Katch-McArdle, which uses lean mass, does better.

Common Uses for Mifflin-St Jeor Calculator

  • Calculate BMR with the current clinical standard formula
  • Compare Mifflin-St Jeor with other equations
  • Build a calorie target from a trusted base

Frequently Asked Questions

What is the Mifflin-St Jeor formula?
For men: (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5. For women, the same with −161 instead of +5.
Why is Mifflin-St Jeor preferred?
Studies find it the most accurate of the common equations for most adults, and it needs only weight, height, age and sex. It tends to slightly overestimate in obese individuals and underestimate in very muscular ones.
Does it work without body fat data?
Yes — that is its main advantage. If you do know your body fat percentage, Katch-McArdle may be more accurate because it works from lean mass.

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