Lean Body Mass Calculator
Estimate lean body mass from your body weight and body fat percentage. Informational only, not medical advice.
Lean body mass is estimated as total weight × (1 − body fat fraction).
Privacy: runs locally in your browser. No values are stored or transmitted.
How it works
This calculator uses lean body mass = total body weight × (1 − body fat fraction). Fat mass is then the remainder of total body weight.
Examples
- 70 kg at 20% body fat → lean body mass ≈ 56 kg
- 154 lb at 18% body fat → lean body mass ≈ 126.28 lb
- Useful for simple body composition estimates
FAQ
- What is lean body mass?
Lean body mass is body weight minus fat mass. It includes muscle, bone, organs, water, and other non-fat tissue.
- Is this the same as muscle mass?
No. Lean body mass includes muscle, but it also includes other non-fat tissue such as bone, water, and organs.
- How is lean body mass estimated here?
This calculator uses your body weight and body fat percentage to estimate how much of your weight is non-fat mass.
- Can I use pounds or kilograms?
Yes. This calculator supports both metric and imperial input.
- Are my values stored?
No. All calculations run locally in your browser.