Lean Body Mass Calculator
Estimate your lean body mass using your age, gender, height, and weight. Choose metric or imperial units to calculate your estimated lean mass and body composition.
Your Lean Body Mass Results
What Is Lean Body Mass?
Lean body mass (LBM) is the estimated weight of everything in your body except body fat. It includes muscles, bones, organs, connective tissue, and body water.
Lean body mass is different from muscle mass because LBM includes more than just muscle tissue.
How Is Lean Body Mass Calculated?
This calculator uses the Boer formula to estimate lean body mass from your height, weight, and sex.
For men:
LBM = (0.407 × weight in kg) + (0.267 × height in cm) − 19.2
For women:
LBM = (0.252 × weight in kg) + (0.473 × height in cm) − 48.3
Why Is Lean Body Mass Important?
Tracking lean body mass can provide additional context when monitoring changes in body weight and body composition.
- Helps distinguish lean tissue from total body weight.
- Can provide useful context during weight-loss or weight-gain goals.
- Can be used alongside body fat percentage and BMI for a broader view of body composition.
- May help track changes over time when measurements are taken consistently.
Lean Body Mass vs. Muscle Mass
Lean body mass and muscle mass are not the same thing. Muscle is only one component of lean body mass. LBM also includes bones, organs, connective tissue, and body water.
Important Limitations
This calculator provides an estimate, not a direct measurement of your body composition. Different formulas and measurement methods can produce different results.
For a more detailed assessment, professional methods such as DEXA or other validated body-composition techniques may provide more precise measurements.
Related Health Calculators
Want to understand your body composition from another perspective? Try the WeightChecker Body Fat Calculator or BMI Calculator.