Lean Body Mass Calculator

Gender

Weight

Height

Body Fat % (Optional)

Results

Boer Formula

James Formula

Hume Formula

Average LBM: -

Fat Mass: -

Formulas:
If Body Fat is given: LBM = Weight × (1 - Body Fat % / 100)
Boer (Male): LBM = 0.407 × W + 0.267 × H - 19.2
Boer (Female): LBM = 0.252 × W + 0.473 × H - 48.3

Examples

Example 1: 70kg, 175cm Male → LBM ~56kg
Example 2: 60kg, 160cm Female → LBM ~42.5kg
Example 3: 80kg with 15% Body Fat → LBM = 68kg

Frequently Asked Questions

What is Lean Body Mass?

LBM is the weight of your body minus your fat weight. It includes organs, skin, bones, body water, and muscle mass.

Why use different formulas?

Different scientists developed formulas based on different sample populations, so using an average often gives the best estimate.

Is LBM the same as muscle mass?

No, LBM includes muscle, but also bones, organs, and water. Muscle mass is only a portion of LBM.

How can I measure exact body fat?

The most accurate methods are DEXA scans, hydrostatic weighing, or using skinfold calipers with a professional.