BMR calculator.
What your body burns at rest, across three trusted formulas.
About you
Your basal metabolic rate
Mifflin-St Jeor, the current research standard.
Your TDEE at each activity level
How this calculator works
BMR is your basal metabolic rate: the energy your body spends just staying alive, before a single step or rep. It is the floor under every calorie target. This calculator runs three published equations side by side.
Harris-Benedict (male) = 88.362 + 13.397 × kg + 4.799 × cm − 5.677 × age
Harris-Benedict (female) = 447.593 + 9.247 × kg + 3.098 × cm − 4.330 × age
Katch-McArdle = 370 + 21.6 × lean body mass (kg)
Mifflin-St Jeor is the headline number because it is the current research standard for the general population. Harris-Benedict is the older classic and usually reads slightly higher. Katch-McArdle ignores age and sex entirely and works from lean body mass instead, which makes it the most accurate option for lean people who actually know their body fat percentage. Add yours in the optional field to unlock it.
From BMR to a real calorie target
You never eat at BMR. Daily life and training sit on top of it, which is what the activity preview rows show: your Mifflin-St Jeor BMR multiplied by the standard factors from 1.2 (sedentary) to 1.9 (very active). That product is your TDEE, the number diets are actually built from.
Ready to set a target? The TDEE calculator adds goal adjustments for cutting and gaining, and the macro calculator turns the result into grams on a plate.
More free calculators.
The math coaches do every day, as free tools. No signup.Calculators are nice. Coaching is better.
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