Lean Body Mass (LBM) Calculator
Measure What Matters — Beyond the Scale
The Withings Body Smart Scale accurately measures weight, fat percentage, and body composition, giving you data to calculate your lean body mass. Wi-Fi and Bluetooth enabled, it syncs with Apple Health for seamless tracking.
Shop Withings Body Smart ScaleAbout Lean Body Mass (LBM) Calculator – Boer Formula
The Lean Body Mass (LBM) Calculator estimates the weight of your body excluding fat, based on the Boer (1984) formula. LBM represents the total mass of muscles, bones, organs, and water — everything except stored body fat.
- Male: LBM = 0.407 × weight(kg) + 0.267 × height(cm) − 19.2
- Female: LBM = 0.252 × weight(kg) + 0.473 × height(cm) − 48.3
The Boer equation is a widely accepted clinical model due to its simplicity and good accuracy across adult populations. This calculator supports both metric and US units, automatically converting inputs to centimeters and kilograms. It also provides an estimate of fat mass and body fat percentage derived from your total body weight and LBM.
These calculations are for informational and educational use only and should not replace professional health or medical assessments.
FAQ
- What is Lean Body Mass (LBM)? Lean Body Mass is your total body weight minus fat mass — it includes muscle, bone, organs, and body water.
- Which formula does this calculator use? This calculator uses the Boer (1984) formula, a clinically validated method for estimating LBM in men and women based on height and weight.
- How accurate is the Boer formula? The Boer equation provides a reliable population-level estimate. Individual results may differ slightly depending on body type, muscle mass, and hydration.
- How is body fat percentage estimated from LBM? Fat mass ≈ total weight − LBM, and body fat % = (fat mass ÷ total weight) × 100. This is an indirect but useful estimation method.
- Can I use pounds and inches? Yes. You can enter height in cm, in, or ft+in and weight in kg or lb; the calculator converts everything automatically.
- What is a typical LBM for adults? For an average healthy male, LBM is about 75–85% of total body weight; for females, it’s roughly 65–75%.
Disclaimer
This calculator is for educational and informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
References
- Boer P. (1984). Estimated lean body mass as an index for normalization of body fluid volumes in humans. American Journal of Physiology, 247(4): F632–F639.
- James WPT, et al. (1988). Body composition in health and disease. Clinical Endocrinology and Metabolism.
- CDC – Assessing Your Weight and Body Composition.