Lean Body Mass Calculator
Estimate adult lean body mass with Boer, James, and Hume formulas, compare methods, and optionally compare against a known body-fat percentage.
This calculator does not measure body composition. It estimates adult lean body mass from height, weight, and sex; DEXA, MRI, BodPod, calipers, or bioimpedance can give different values.
Estimate Lean Body Mass
This calculator estimates adult lean body mass from weight, height, and sex using Boer, James, and Hume equations. It also lets you compare a formula result with a separate known body-fat percentage.
Lean mass when body fat percentage is already known.
Formula estimate
Lean body mass formulas do not measure body composition. Results can diverge with edema, pregnancy, severe obesity, pediatric use, or unusually high athletic muscle mass.
How To Use The Output
- Use one primary formula consistently when tracking changes over time.
- Compare Boer, James, and Hume to see how sensitive the estimate is to equation choice.
- Use a measured body-fat percentage when you have one, but remember that measurement methods also vary.
Frequently Asked Questions
Sources and References
- Lean Body Mass CalculatorCalculator.net
- Estimated lean body mass as an index for normalization of body fluid volumes in humansPubMed
- Lean Body Mass Calculator - Boer, James & Hume FormulasTrainCalc
Calculations are based on the listed reference sources. Links open in a new tab.
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