Lean Body Mass Calculator

What Lean Body Mass Includes

Lean body mass is total body weight minus fat mass. It includes skeletal muscle, organs, bone, connective tissue, and body water, so it is not the same as muscle mass.

This calculator predicts lean mass from height and weight; it does not measure tissue directly.

Boer Equations

W is weight in kilograms and H is height in centimeters. Imperial inputs are converted before calculation.

Worked Example

For a man weighing 70 kg at 175 cm, estimated lean mass is (0.407 x 70) + (0.267 x 175) - 19.2 = 56.0 kg, or about 80.0% of total body weight.

How To Use The Estimate

Use the value as rough body-composition context or as one input in formulas that explicitly call for estimated lean mass. Changes smaller than normal formula and measurement error should not be treated as proven tissue gain or loss.

Limits

The original equations were fitted to particular adult samples and may be less accurate for children, pregnancy, edema, very muscular athletes, older adults, or people with body proportions outside those samples. DEXA and other clinical methods answer different questions and may be more appropriate when accuracy matters.