What is lean body mass?
Lean body mass is your total body weight minus fat mass. It includes muscle, bones, organs, connective tissue, and body water.
How is lean body mass calculated?
Lean body mass is calculated by multiplying body weight by one minus body fat percentage. Fat mass is body weight multiplied by body fat percentage.
When to use this calculator
Use lean body mass to track body composition, set protein targets, or understand whether weight changes are likely coming from fat or lean tissue.
Limitations
The result depends on the accuracy of your body fat percentage. Estimates from tape measurements, smart scales, or visual charts can differ from professional body composition testing.