Lean Body Mass Calculator
Estimate your lean body mass and fat mass from your weight and height.
Sex
kg
cm
18.6 kg
23.2 %
Boer
Formula
Examples
| Input | Result |
|---|---|
| Male, 80 kg, 180 cm | LBM ≈ 61.5 kg |
About this calculator
Lean body mass (LBM), also called fat-free mass, is the weight of everything in your body except fat: muscle, bone, organs, and water. Knowing it is useful for setting protein targets, judging muscle gain or loss, and for clinical drug dosing. The Boer formula estimates LBM from total weight and height with separate coefficients for men and women.
Subtracting lean mass from total body weight gives an approximate fat mass, from which a rough body fat percentage follows. Predictive formulas like Boer are convenient but are estimates; for precise composition, methods such as DEXA scanning, hydrostatic weighing, or bioelectrical impedance are more accurate. Use this result to track trends rather than as an exact figure.
Frequently asked questions
It is your total body weight minus fat — including muscle, bone, organs, and body water. It is also called fat-free mass.
It helps set protein intake, track muscle changes during training or dieting, and is used clinically to dose certain medications.
It is a solid predictive estimate for most adults, but scans like DEXA give more precise composition for athletes or unusual body types.
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