Calculate lean body mass using the Boer formula
The Boer equation predicts lean mass from height and weight only, so fat mass and body-fat % are rough population-level estimates and can be several percentage points off for muscular or very lean people. It is not a body-composition measurement (DEXA, BIA or skinfold methods are more direct). Not medical advice.
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Lean Body Mass is built on published formulas and reference ranges from established health sources. We revisit it periodically as guidance evolves; the "Last reviewed" date above shows when that last happened. If something looks wrong, tell us with the feedback button in the bottom-right corner.