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Lean Body Mass Calculator

Calculate lean body mass and fat mass from your weight and height using the Boer formula.

Uses the Boer formula, a widely used estimate based on total body weight and height.

Lean body mass

56 kg

Estimated fat mass14 kg
Total weight70 kg

Lean body mass (LBM) is your total weight minus fat mass, useful for tracking body composition and setting protein targets. This calculator uses the Boer formula with metric or imperial inputs, calculated instantly in your browser.

How to use

  1. Choose your sex and preferred unit system.
  2. Enter your weight and height.
  3. Read your estimated lean body mass and fat mass.

Frequently asked questions

What is the Boer formula?
The Boer formula estimates lean body mass from total weight and height, separately calibrated for men and women.
How is fat mass calculated?
Fat mass is your total weight minus the estimated lean body mass.
Is this as accurate as a DEXA scan?
No, formula-based estimates are less precise than clinical body composition scans, but they're a useful free approximation.

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