Free Lean Body Mass (LBM) Calculator (Boer, James & Hume) Online
Calculate Lean Body Mass (LBM) and Fat Mass in kilograms and pounds using the clinical Boer, James, and Hume comparative formulas. — 100% free online utility, zero sign-up, zero paywalls, and private client-side processing.
How It Works
Select Biological Sex
Choose Male or Female for sex-specific equation constants.
Enter Height & Weight
Input height in cm/inches and weight in kg/lbs.
Review Multi-Formula Output
Compare Boer (preferred in hospitals), James, and Hume calculations.
View Fat Mass Balance
See exact breakdown between lean tissue and total adipose fat mass.
Frequently Asked Questions
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