Lean Body Mass Calculator
Calculate your lean body mass using multiple formulas and estimate your body fat percentage. Understand your body composition better.
Calculate Your Lean Body Mass
Your Lean Body Mass Results
Enter your information to calculate lean body mass
Understanding Lean Body Mass
Lean Body Mass (LBM) is the total weight of your body minus all the fat. It includes bones, muscles, water, ligaments, tendons, and internal organs. Lean body mass is important for metabolism, strength, and overall health.
LBM Calculation Formulas
Boer Formula
Most commonly used for medical purposes
James Formula
Based on DHSS/MRC research on obesity
Hume Formula
Clinical pathology research-based
Body Fat Percentage Ranges
Essential Fat
Men: 2-5%, Women: 10-13%. Minimum required for normal physiological function.
Athletes
Men: 6-13%, Women: 14-20%. Typical range for competitive athletes.
Fitness
Men: 14-17%, Women: 21-24%. Good fitness level for most people.
Average
Men: 18-24%, Women: 25-31%. Average range for most adults.
Lean Body Mass vs Fat-Free Mass
Lean Body Mass (LBM)
- • Includes bones, muscles, water, and organs
- • Contains some essential fat
- • Used for medical dosing
- • 60-90% of total body weight
Fat-Free Mass (FFM)
- • Excludes all fat including essential fat
- • More precise measurement
- • Used in research settings
- • 2-3% difference from LBM (men)
Important Note: Lean body mass calculations are estimates based on statistical formulas. They don't account for individual variations in body composition, muscle mass, or bone density. For the most accurate assessment, consider professional body composition testing methods such as DEXA scans, hydrostatic weighing, or bioelectrical impedance analysis.
