Lean mass guide
Lean Body Mass Calculator in Pounds
Calculate lean body mass in pounds and kilograms from imperial body weight, height, and optional body fat percentage.
Last updated: · Reviewed by the Lean Mass Calculator editorial team
Who this page is for
Imperial-unit users who want lean mass and fat mass in pounds.
Start with the main lean mass calculator, then use the related tools below when you need body fat, FFMI, protein, or calorie context.
Interactive Calculator
Use this calculator to find your specific numbers before continuing with the guide.
Imperial inputs to use
Select pounds for body weight and ft / in for height. The calculator converts to metric internally because the published equations use kilograms and centimeters.
Results are shown in both kilograms and pounds so you can use them for nutrition targets or body-composition logs.
When pounds are most useful
Fat mass in pounds is easy to compare with scale-weight changes. For example, a 10 lb loss with stable lean mass suggests most of the change came from fat.
For protein targets, the site still calculates from lean mass in kilograms because research ranges are usually stated in g/kg.
Frequently asked questions
What is the lb formula for lean mass?
With body fat percentage, lean mass lb = body weight lb x (1 - body fat percentage / 100).
Why does the calculator also show kg?
Most lean-mass equations and protein targets are written in metric units, so showing both avoids hidden conversions.
Sources & references
The estimates on this page use published lean body mass equations and clinical reference ranges. See the full reference charts on the lean body mass chart hub.
- Estimated lean body mass as an index for normalization of body fluid volumes — Boer P, American Journal of Physiology (PubMed) (1984)
- Percent Body Fat Norms and Reference Ranges — American Council on Exercise (ACE)
- Body Composition — Reference Information — National Institutes of Health (NCBI Bookshelf)