Lean Body Mass Calculator
Estimate your lean body mass (everything except fat mass) using the Boer formula, based on your weight, height, and sex.
- Free to use
- No registration required
- Works on all devices
- Last updated
- 13-09-2026
Your result
58.1 kg
Lean body mass
AI explanation
Formula
Men: LBM = 0.407×weight + 0.267×height − 19.2. Women: LBM = 0.252×weight + 0.473×height − 48.3Worked example
Male, 75kg, 175cm
| Field | Value |
|---|---|
| Weight | 75 |
| Height | 175 |
| Sex | male |
| Lean body mass | 58.1 |
Assumptions
- Uses the Boer formula (1984), validated against body-density measurements and one of the more accurate weight/height-based LBM estimates available.
- Fat mass is derived as total weight minus estimated lean body mass, so its accuracy depends on the LBM estimate.
Frequently asked questions
What is lean body mass?
Lean body mass is your total bodyweight minus fat mass — it includes muscle, bone, organs, and water content.
Why do men and women have different LBM formulas?
The Boer formula's sex-specific constants reflect average differences in body composition and fat distribution between men and women in the population it was derived from.
How accurate is a weight/height-based LBM formula compared to a body scan?
Formula-based estimates are convenient but less precise than direct methods like DEXA or bioelectrical impedance, which measure body composition rather than estimating it from two measurements.
Related calculators
Related articles
Sources
- Estimated lean body mass as an index for normalization of body fluid volumes in humans — American Journal of Physiology. Effective 01-10-1984, checked 13-09-2026.
This calculator provides a general estimate only and does not constitute personalized medical advice. For a precise body composition measurement, consider a DEXA scan.
Report a calculation issue