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Lean Body Mass Calculator

Calculate Your Lean Body Mass

Quick Examples

Lean Body Mass Analysis

Enter your weight and body fat percentage above to calculate lean body mass

Medical Disclaimer

This calculator is for informational purposes only and should not be used as medical advice.

• Lean body mass calculations are estimates based on body fat percentage

• Body fat percentage measurements can vary based on method and accuracy

• This tool is not a substitute for professional medical advice, diagnosis, or treatment

• Always consult with your healthcare provider for accurate body composition analysis

• Professional body composition testing provides more accurate results

• Never make significant changes to your fitness routine without medical consultation

About Lean Body Mass Calculator

This lean body mass calculator estimates your lean body mass based on your total weight and body fat percentage. Lean body mass includes muscles, bones, organs, and water, but excludes body fat.

What is Lean Body Mass?

Lean body mass (LBM) is the weight of everything in your body except fat. This includes muscles, bones, organs, skin, and water. It's an important indicator of fitness and health, as higher lean mass typically correlates with better metabolism and overall health.

Calculation Formula:

Lean Body Mass = Total Weight × (1 - Body Fat Percentage / 100)
For example: 180 lbs × (1 - 15/100) = 180 × 0.85 = 153 lbs lean body mass

Lean Mass Index (LMI):

Males:

  • Low: <18.5 kg/m²
  • Normal: 18.5 - 22.0 kg/m²
  • High: >22.0 kg/m²

Females:

  • Low: <16.0 kg/m²
  • Normal: 16.0 - 19.0 kg/m²
  • High: >19.0 kg/m²

Body Fat Percentage Ranges:

Males:

  • Essential: 2-5%
  • Athletes: 6-13%
  • Fitness: 14-17%
  • Average: 18-24%
  • Obese: >25%

Females:

  • Essential: 10-13%
  • Athletes: 14-20%
  • Fitness: 21-24%
  • Average: 25-31%
  • Obese: >32%

Important Notes:

  • Body fat percentage can be measured using various methods (calipers, DEXA, bioelectrical impedance)
  • Accuracy depends on the measurement method and technique
  • Lean body mass naturally decreases with age (sarcopenia)
  • Strength training can help maintain and increase lean mass
  • Proper nutrition, especially protein intake, supports lean mass
  • Consult professionals for accurate body composition assessment