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Mifflin-St Jeor Clinical Gold Standard

Basal Metabolic Rate (BMR) Calculator

Calculate the exact baseline calories your body expends at complete rest using validated physiological equations.

yrs
cm
kg
18%
5% (Athletic)20% (Average)40%+ (Higher Adiposity)
Resting Energy NeedsMifflin-St Jeor
1,728kcal / day

Your body burns approximately 1,728 calories daily at complete physical and digestive rest.

Comparative Scientific Estimates
Mifflin-St Jeor (1990):1,728 kcal
Katch-McArdle (LBM):1,698 kcal
Harris-Benedict (Revised):1,754 kcal
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Daily Energy Expenditure (TDEE Multipliers)

Physical Activity Level (PAL) multipliers established by the FAO/WHO/UNU joint expert consultation applied to your calculated BMR:

Activity LevelPAL FactorDaily Energy NeedsTypical Lifestyle
Sedentary1.2002,074 kcalDesk job, minimal incidental movement
Lightly Active1.3752,376 kcalLight exercise / walking 1–3 days/week
Moderately Active1.5502,678 kcalModerate training 3–5 days/week
Very Active1.7252,981 kcalHard training / sports 6–7 days/week
Extra Active / Athlete1.9003,283 kcalTwice daily heavy athletic training or physical job

BMR Frequently Asked Questions

What is Basal Metabolic Rate (BMR)?

Basal Metabolic Rate (BMR) is the minimum amount of energy (measured in calories per day) required to sustain vital bodily functions at complete physical and digestive rest, including breathing, cellular repair, circulation, protein synthesis, and ion transport.

Which BMR formula is the most scientifically accurate?

The Mifflin-St Jeor equation (1990) is clinically recognized by the Academy of Nutrition and Dietetics as the most accurate predictive equation for healthy individuals, with a margin of error within 10% of indirect calorimetry measurements. If body fat percentage is known, the Katch-McArdle formula is equally accurate as it accounts directly for lean body mass.

What is the difference between BMR and TDEE?

BMR represents only your baseline survival calories without movement. Total Daily Energy Expenditure (TDEE) accounts for your BMR multiplied by your physical activity level (PAL) plus the Thermic Effect of Food (TEF) and exercise.

How can I increase my resting metabolic rate?

Building and preserving lean skeletal muscle through progressive resistance training is the most sustainable way to elevate resting metabolic rate, as muscle tissue is more metabolically active than adipose tissue even at rest.

Scientific References & Peer-Reviewed Literature

  1. Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. (1990). A new predictive equation for resting energy expenditure in healthy individuals. The American Journal of Clinical Nutrition, 51(2), 241–247. PMID: 2305711.
  2. Roza AM, Shizgal HM. (1984). The Harris Benedict equation reevaluated: resting energy requirements and the body cell mass. The American Journal of Clinical Nutrition, 40(1), 168–182. PMID: 6741850.
  3. McArdle WD, Katch FI, Katch VL. (2014). Exercise Physiology: Nutrition, Energy, and Human Performance. 8th edition. Wolters Kluwer Health / Lippincott Williams & Wilkins.
  4. FAO/WHO/UNU. (2004). Human energy requirements: Report of a Joint FAO/WHO/UNU Expert Consultation. FAO Food and Nutrition Technical Report Series 1, Rome.
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