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Lean Body Weight (LBW)
Estimates fat-free body weight — the Boer formula is shown as primary (a widely-used modern clinical reference), with James shown alongside since the two formulas can diverge meaningfully, especially at higher BMI.
For healthcare professionals.These calculate a score or a measurement from values you enter. They do not diagnose, and they are no substitute for clinical judgement. If you are a patient, discuss any result with your own doctor rather than acting on it.
kg
cm
Enter the values above to see the result.
Source
- Boer P. Estimated lean body mass as an index for normalization of body fluid volumes in humans. Am J Physiol. 1984;247(4 Pt 2):F632-636.
- James WPT. Research on Obesity: A Report of the DHSS/MRC Group. London: HMSO; 1976.
Shown for reference and checked against the source above. Confirm against current guidance before acting on it, and use your own clinical judgement.
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