Lean Body Mass Calculator: The Complete Guide
Find out how much of your body is lean tissue. Enter your sex, height, and weight to estimate your lean body mass and fat mass using the Boer formula.
Who the Lean Body Mass Calculator is for
Athletes and dieters who want to track lean mass rather than just total weight.
How to use the Lean Body Mass Calculator
- Type your values into the fields above — pick your currency or units where the calculator offers them.
- Results update automatically as you type; there's no submit button and nothing is sent to a server.
- Adjust any input to compare scenarios, then copy the result with a single click.
How it works
Boer formula: for men, LBM = 0.407 × weight(kg) + 0.267 × height(cm) − 19.2; for women, LBM = 0.252 × weight(kg) + 0.473 × height(cm) − 48.3. Fat mass is total weight minus LBM.
Features
- Boer formula
- Lean and fat mass
- Metric or imperial
- Male & female
Why lean body mass matters
Lean body mass is everything in your body that isn't fat — muscle, bone, organs, and water. Tracking it helps you tell whether weight changes come from muscle or fat, which scale weight alone can't reveal. It's also used to guide protein needs and medication dosing.