Lean Body Mass Calculator

Estimate LBM | Boer, James & Hume Formulas | Body Composition Analysis

📏 Height (cm)

⚖️ Weight (kg)

⚥ Gender

🎂 Age (optional)

LBM = Total Weight - Fat Mass | 3 Medical Formulas Averaged

📖 How to Use This Lean Body Mass Calculator

Enter your height, weight, and gender to get your estimated lean body mass using three validated medical formulas: Boer, James, and Hume.

💪 What is Lean Body Mass (LBM)?

Lean Body Mass is the total weight of your body minus all fat mass. It includes muscle, bones, organs, connective tissue, and water. Unlike BMI which only considers height and weight, LBM provides a better picture of body composition.

📊 LBM Formulas

Boer (1984): Male: 0.407×W + 0.267×H - 19.2 | Female: 0.252×W + 0.473×H - 48.3
James: Based on height and weight coefficients
Hume (1966): Male: 0.32810×W + 0.33929×H - 29.5336 | Female: 0.29569×W + 0.41813×H - 43.2933

💡 Why LBM Matters

Muscle burns 3x more calories than fat at rest
LBM increases with strength training
Used for medical drug dosing
Preserving muscle reduces fall risk with age

🔥 How to Increase LBM

Strength training 2-4x per week
Protein intake: 1.6-2.2 g per kg body weight
Sleep 7-9 hours for recovery
Progressive overload in workouts

❓ Frequently Asked Questions

❓ Which LBM formula is most accurate? ▼

The Boer formula is considered most accurate for the general population. DEXA scans provide the most accurate clinical measurement.

❓ What is a good LBM percentage? ▼

Men: 75-85% of total weight. Women: 65-75% due to higher essential body fat. Higher LBM indicates better fitness.

❓ Does age affect LBM? ▼

Yes, LBM naturally decreases with age (sarcopenia). After 30, adults lose 3-8% of muscle per decade. Strength training can reverse this.

❓ Can I calculate fat mass from LBM? ▼

Yes! Fat Mass = Total Weight - LBM. Example: 80kg weight - 60kg LBM = 20kg fat mass (25% body fat).