Free Lean Body Mass Calculator
Calculate your lean body mass (fat-free mass) based on your weight and body fat percentage.
lbs
%
Lean Body Mass (lbs)
144.0 lbs
Lean Body Mass (kg)65.3 kg
Fat Mass (lbs)36.0 lbs
Lean Body Mass (lbs) vs Body Weight
Lean Body Mass Formula
Lean Body Mass = Weight x (1 - Body Fat % / 100)
Lean body mass includes everything except fat: muscles, bones, organs, water, and other tissues.
Example Calculation
A 180 lb person with 20% body fat.
- 01Lean mass = 180 x (1 - 20/100) = 180 x 0.80 = 144 lbs
- 02In kg = 144 x 0.4536 = 65.3 kg
- 03Fat mass = 180 x 0.20 = 36.0 lbs
Frequently Asked Questions
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