Lean Body Mass Calculator
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Results
| Formula | LBM (kg) | LBM (lbs) |
|---|---|---|
| Boer Formula (1984) | — | — |
| James Formula (1976) | — | — |
| Hume Formula (1966) | — | — |
Understanding Lean Body Mass (LBM)
Lean Body Mass (LBM) represents the weight of your body excluding all fat tissue. This contains muscles, bones, organs, connective tissue, and water content.
The 3 Major Formulas
LBM calculation models use weight ($W$ in kg) and height ($H$ in cm) under three distinct clinical formulas:
- **Boer Formula (1984):**
- Men: $\text{LBM} = 0.407 \times W + 0.267 \times H - 19.2$
- Women: $\text{LBM} = 0.252 \times W + 0.473 \times H - 48.3$
- **James Formula (1976):**
- Men: $\text{LBM} = 1.1 \times W - 128 \times (W / H)^2$
- Women: $\text{LBM} = 1.07 \times W - 148 \times (W / H)^2$
- **Hume Formula (1966):**
- Men: $\text{LBM} = 0.32810 \times W + 0.33929 \times H - 29.5336$
- Women: $\text{LBM} = 0.29569 \times W + 0.41013 \times H - 12.9716$
Disclaimer. LBM estimates are statistical projections based on averages. They can under- or over-estimate lean mass in individuals with exceptional muscular development (e.g. bodybuilders) or unusual water retention.