Calculate your lean body mass using Boer, James, and Hume formulas.
Lean body mass (LBM) is your total weight minus fat — it includes muscle, bone, organs, and water. This calculator uses three validated formulas (Boer, James, Hume) and averages them for a more reliable estimate.
Three formulas compared
Boer, James, and Hume results side by side.
Body fat estimate
Derived from weight minus lean mass.
Averaged result
Averages all three for a balanced estimate.
Metric & imperial
Full dual-unit support.
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