About this tool
Estimate lean body mass (LBM) — the weight of everything except fat. Useful for dosing medications and assessing muscle mass.
Formula
Boer (1984): Men: LBM = 0.407·W + 0.267·H − 19.2. Women: LBM = 0.252·W + 0.473·H − 48.3. (W=kg, H=cm.)
Worked example
Male, 70 kg, 175 cm → LBM ≈ 0.407·70 + 0.267·175 − 19.2 ≈ 56 kg. Fat mass ≈ 14 kg.
Notes
Other formulas (James, Hume) give similar estimates ±2 kg. For clinical drug dosing, the most appropriate formula depends on the medication.