What is lean body mass?
Lean body mass (LBM) is your total body weight minus fat mass. It includes muscle, bone, organs, and water. LBM is important for metabolism, strength, and overall health. Higher LBM typically means higher metabolic rate.
Lean Body Mass Calculator
Calculate your lean body mass to estimate muscle and non-fat weight.
This calculator provides estimates. For a more precise assessment, use body fat percentage from a clinical or professionally administered method. Without body fat data, the Boer formula provides a rough estimate based on weight.
How to use this calculator
- Enter the requested measurements or values.
- Choose the unit system or options that match your situation.
- Review the result and interpretation.
- Use the number as an educational estimate, not a diagnosis or prescription.
Example
Use the calculator to estimate a health or fitness number, then compare it with trends over time and other relevant context.
These tools are for education and planning. They do not replace medical advice.
Frequently Asked Questions
How is lean body mass calculated?
If you know your body fat percentage, LBM = weight × (1 - body fat %). Without body fat data, this calculator uses the Boer formula, which estimates LBM based on weight. For more accuracy, use a body fat percentage from a DEXA scan or other measurement.
Why is lean body mass important?
LBM determines your metabolic rate, strength, and functional capacity. Preserving LBM during weight loss is crucial to avoid muscle loss and metabolic slowdown. Strength training and adequate protein help maintain LBM.
How can I increase lean body mass?
Build LBM through progressive strength training and adequate protein intake (1.6-2.2g per kg body weight). Eat at a slight calorie surplus if gaining muscle is your primary goal. Consistency and patience are key.