Lean Body Mass Calculator
LBM via the Boer, Hume or James formula (selectable) — see how the three published equations bracket your lean mass.
Lean body mass is everything that isn't fat — muscle, bone, organs, water. The Boer formula is the one contrast-dose calculations and many drug doses reference. These height-weight regressions assume average builds; tape or skinfold body-fat methods respond better to training changes.
Formula
For general information only — not medical advice, a diagnosis or a treatment plan. Consult a qualified healthcare professional before making health, diet, medication or exercise decisions.
LBM via the Boer, Hume or James formula (selectable) — see how the three published equations bracket your lean mass. The Lean Body Mass Calculator is a free, private lean body mass tool — every result computes instantly in your browser with no sign-up and no data upload.
About Lean Body Mass Calculator
Lean body mass is everything that isn't fat — muscle, bone, organs, water. It applies Boer M: 0.407W + 0.267H − 19.2 · F: 0.252W + 0.473H − 48.3. Use the Lean Body Mass Calculator to get an instant, clearly-explained result with the working shown step by step — free, private and with the source method cited.
How to use Lean Body Mass Calculator
- 1Enter your details in the Lean Body Mass Calculator input fields above.
- 2The result updates instantly with the working and reference bands shown.
- 3Adjust any value to explore how it changes the outcome — it's free and unlimited.
Why use Lean Body Mass Calculator?
- ✓Instant lean body mass result that recomputes as you type — no waiting, no page reloads
- ✓100% client-side: your health data never leaves your browser
- ✓Shows the actual formula and your numbers substituted in, so you can see exactly how the result is reached
- ✓Based on published, citable sources (Boer P, Am J Physiol 1984;247:F632-6)
- ✓Free forever with no sign-up, account or app install
Frequently asked questions
How does the Lean Body Mass Calculator work?+
Lean body mass is everything that isn't fat — muscle, bone, organs, water. The calculation uses the formula: Boer M: 0.407W + 0.267H − 19.2 · F: 0.252W + 0.473H − 48.3. Everything runs instantly in your browser as you type — your inputs are never uploaded.
Is the Lean Body Mass Calculator accurate, and what is it based on?+
The method is traceable to authoritative sources, including Boer P, Am J Physiol 1984;247:F632-6; Hume R, J Clin Pathol 1966;19:389-91. Results are estimates — individual variation always applies, so treat the output as a well-grounded starting point.
Is the Lean Body Mass Calculator free and private?+
Yes. It's completely free with no sign-up, and all computation happens locally in your browser, so none of your health data ever leaves your device.
Can I use this for medical decisions?+
This tool is for general information only and is not medical advice. Always consult a qualified healthcare professional before making health decisions.
What can I use the Lean Body Mass Calculator for?+
It's commonly used for lean body mass, lbm calculator, boer formula. LBM via the Boer, Hume or James formula (selectable) — see how the three published equations bracket your lean mass.
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