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Harris-Benedict BMR calculator

The original Harris-Benedict equation dates to 1919 and was revised by Roza and Shizgal in 1984. This uses the revised coefficients.

years
Basal metabolic rate
1696kcal/day
= Exact BMR (Harris-Benedict)
Daily energy needs
2332 kcal/day
Show the working
  1. Weight = 70
  2. Height = 175
  3. Age = 30
  4. Sex = 1
  5. Activity level = 1.375
  6. Basal metabolic rate = 1 > 0 ? 88.362 + 13.397*70 + 4.799*175 - 5.677*30 : 447.593 + 9.247*70 + 3.098*175 - 4.330*30 = 1695.67
  7. Daily energy needs = 1695.67 * 1.375 = 2331.54

Values are shown to six significant figures here; the arithmetic itself runs on exact fractions and is only rounded where a number is printed.

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    The formula

    • Men: BMR = 88.362 + 13.397 W + 4.799 H - 5.677 A
    • Women: BMR = 447.593 + 9.247 W + 3.098 H - 4.330 A

    Harris-Benedict tends to read about 5% higher than Mifflin-St Jeor for the same person.

    This is a population formula, not a diagnosis. Individual metabolism, body composition and medical history all move the real answer, so treat the number as a starting point and talk to a clinician about anything that matters.

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