About the Lean Body Mass Calculator
Estimate how much of your weight is muscle, bone, organs and water rather than fat, using three established formulas or your measured body-fat percentage.
Key features
- Boer, James and Hume formulas
- Or from your body-fat percentage
- Fat mass estimate
- Metric or imperial units
- Men and women
- Instant results
Estimate your lean body mass
Find out how much of your weight is lean tissue rather than fat. Enter your height and weight, and your body-fat percentage if you know it.
The formulas (kg and cm)
| Formula | Men | Women |
|---|---|---|
| Boer | 0.407W + 0.267H − 19.2 | 0.252W + 0.473H − 48.3 |
| James | 1.1W − 128(W/H)² | 1.07W − 148(W/H)² |
| Hume | 0.32810W + 0.33929H − 29.5336 | 0.29569W + 0.41813H − 43.2933 |
Example
A man who is 175 cm and 70 kg has an estimated lean body mass of about 56 kg (Boer), so roughly 14 kg of his weight is fat.
Related calculators
Body fat calculator, BMR calculator (Katch-McArdle uses lean mass), and protein intake calculator.
How to use the Lean Body Mass Calculator
- Enter your numbers in the fields above. Units and options can be changed at any time.
- The result updates instantly as you type; there's no calculate button to press.
- Check the breakdown under the main result for the details behind the number.
- Adjust the inputs to compare scenarios, for example a different rate or term.