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BMR Calculator

Basal Metabolic Rate — the calories your body burns at complete rest. The foundation of every calorie target.

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Frequently asked questions

What is BMR?

Calories your body burns at complete rest to maintain basic functions. The floor for any calorie target.

Mifflin-St Jeor vs Harris-Benedict?

Mifflin-St Jeor is more accurate for modern, non-obese populations. Harris-Benedict was developed in 1919 and tends to overestimate.

Does BMR change with age?

Yes — BMR decreases ~1–2% per decade after age 20 due to loss of metabolically active lean mass.