Lean Body Mass Calculator

Lean body mass (LBM) is your total body weight minus all fat mass. It includes muscle, bone, water, organs, and other non-fat tissue. LBM is a useful metric because it reflects your metabolically active tissue — the part of your body that burns calories, produces force, and supports movement.

Lean body mass includes everything that isn't fat — muscle, bone, water, organs, and connective tissue. Muscle mass is only the skeletal muscle component. Roughly 40-50% of lean body mass is skeletal muscle in healthy adults. LBM is easier to estimate because you only need weight and body fat percentage.

Progressive resistance training is the most effective way to increase LBM. Combine it with adequate protein intake (1.6-2.2g per kg of body weight), a slight caloric surplus (200-300 kcal above maintenance), and quality sleep. Consistency over months and years matters more than any single training program.

Lean body mass varies widely based on height, sex, and training history. As a rough guide, men typically have 60-90% of their body weight as LBM, and women 50-80%. Rather than targeting a specific LBM number, focus on gradually increasing it through strength training while maintaining a healthy body fat percentage.