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BMR Calculator (Harris-Benedict)

Estimate basal metabolic rate using the revised Harris-Benedict equation, from age, sex, height, and weight, in metric or imperial units.

BMR (calories/day)
1,696

How it works

This uses the revised Harris-Benedict equation (Roza & Shizgal, 1984), the formula this site's existing Mifflin-St Jeor BMR calculator supersedes in current clinical nutrition guidance, but which is still widely cited in older tools and textbooks. For men: BMR = 88.362 + 13.397×weight(kg) + 4.799×height(cm) − 5.677×age(years). For women: BMR = 447.593 + 9.247×weight(kg) + 3.098×height(cm) − 4.330×age(years).

The formula's coefficients are calibrated for kilograms, centimeters, and years, so imperial entries are converted to metric before the calculation runs and the result comes out identical either way.

Like this site's Mifflin-St Jeor calculator, this is resting energy expenditure only — the calories your body uses at complete rest — not a total daily calorie target, which multiplies this number by an activity factor.

FAQ

Why does this site have two BMR calculators?

Mifflin-St Jeor and Harris-Benedict are both named, published formulas for the same quantity, and they give slightly different numbers. Current dietetics guidance generally favors Mifflin-St Jeor as more accurate for most adults, but Harris-Benedict is still the formula many older calculators, textbooks, and clinical references use — this calculator lets you get that specific number rather than approximating it with the other formula.

Which one should I use?

Mifflin-St Jeor (this site's other BMR calculator) for a general estimate — it's the more recent, more broadly validated formula. Use Harris-Benedict instead if you're comparing against a source, study, or older tool that specifically used it.

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