Lean Body Mass Calculator

Calculated using standard mathematical and industry formulas.

Free online Lean Body Mass Calculator calculator and unit conversion tool for everyday, engineering, and home projects.

How to use this calculator?

  1. Select your gender and unit system.
  2. Enter your total weight and height.
  3. Compare LBM estimates across Boer, James, and Hume clinical formulas.

Formula & calculation method

Boer, James & Hume LBM Formulas

Male Boer LBM = 0.407 × Weight(kg) + 0.267 × Height(cm) − 19.2

Female Boer LBM = 0.252 × Weight(kg) + 0.473 × Height(cm) − 48.3.

Step-by-step calculation example

Male 70 kg at 175 cm: Boer LBM ≈ 55.9 kg (80% lean mass, 20% fat mass).

Key insights to remember

How to interpret your results?

Lean Mass (LBM)

Total weight of all body components excluding non-essential adipose fat.

Fat Mass

The weight of body fat calculated by subtracting average LBM from total weight.

Frequently asked questions

How do I use the Lean Body Mass Calculator calculator?
Enter your numerical input and select desired units to get instant accurate results.
How accurate are the conversions?
Conversions use official ISO conversion factors for maximum precision.
Does it convert metric and imperial units?
Yes, seamless conversions between metric (meters, kg) and imperial (feet, lbs) are supported.
Is my data stored?
No, all calculations execute 100% locally in your browser with zero data logging.
Can I use this for DIY or engineering projects?
Yes, it provides reliable estimates for construction, crafting, science, and everyday math.
What if I enter invalid inputs?
The calculator will display a friendly error prompt if non-numeric values are entered.

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