Lean Body Mass Calculator

Lean body mass (LBM) is your total body weight minus body fat. It includes muscle, bone, organs, connective tissue, and water. LBM is important for metabolism, as lean tissue burns more calories than fat tissue. Higher LBM typically indicates better metabolic health and physical fitness.

LBM can be calculated using formulas like the Boer formula (based on weight, height, and gender) or by using body fat percentage (LBM = weight × (1 - body fat %)). The Boer formula is: Men: 0.407 × weight(kg) + 0.267 × height(cm) - 19.2; Women: 0.252 × weight(kg) + 0.473 × height(cm) - 48.3.

For men, 85-95% LBM (5-15% body fat) is considered healthy, with athletes often at 90-95%. For women, 75-85% LBM (15-25% body fat) is healthy, with athletes at 80-90%. Essential fat is 3-5% for men and 8-12% for women. These ranges vary by age, fitness level, and individual health goals.

Lean body mass includes all non-fat tissue: muscles, bones, organs, water, and connective tissue. Muscle mass refers specifically to skeletal muscle tissue. LBM is always higher than muscle mass alone. For example, if you have 60kg LBM, only about 30-40kg might be actual muscle, with the rest being bones, organs, and other tissues.

Increase LBM through strength training (resistance exercises 3-4 times weekly), adequate protein intake (1.6-2.2g per kg body weight), progressive overload training, sufficient sleep (7-9 hours), caloric surplus for muscle growth, and staying hydrated. Consistency over months and years is key for significant LBM gains.

LBM is crucial for: higher resting metabolism (burns more calories), better insulin sensitivity and blood sugar control, improved bone density, enhanced physical performance and strength, protection against age-related muscle loss (sarcopenia), and better overall health outcomes. Higher LBM is associated with longevity and quality of life.