OhMyCalc

Lean Body Mass Calculator

Calculate your lean body mass, fat mass, and lean-to-fat ratio from weight and body fat percentage.

How to Use the Lean Body Mass Calculator

  1. Enter your body weight in kilograms.
  2. Enter your body fat percentage.
  3. Click Calculate to see your lean body mass and fat mass.
  4. Review the lean-to-fat ratio and use the values to track body composition changes over time.

Quick Reference

FromTo
Men (healthy)15–20% body fat
Men (athletes)6–13% body fat
Women (healthy)20–25% body fat
Women (athletes)14–20% body fat
Essential fat (M)2–5%
Essential fat (F)10–13%

Use Cases

Formula

LBM = weight × (1 − body fat% / 100). Fat mass = weight × body fat% / 100.

Frequently Asked Questions

How to use?
Enter your weight and body fat percentage, then click Calculate to get your lean body mass and fat mass.
Calculation accuracy?
Calculations are performed with high precision.
Is it free?
Yes, all calculators are completely free.