Lean Body Mass Calculator
Compare lean body mass estimates using the Boer, James, and Hume equations.
Boer, James, and Hume produce different estimates; none replaces body-composition measurement.
Estimated result
The entered measurements fall outside these equations' useful range.
Lean-mass estimates
Boer, James, and Hume predict non-fat body mass from weight, height, and the sex variable used by each model.
Differences between equations
Populations and mathematical fits differ. Their average does not replace DXA or another body measurement.
Frequently asked questions
Is lean mass only muscle?
No. It also includes water, bone, organs, and other non-fat tissue.
Is personal data sent to a server?
No. Calculations run locally in your browser and these values are not stored by default.
Can I use the result as medical advice?
No. It is an educational reference and does not replace individual assessment.
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