Free Bioimpedance Body Composition Estimator

Estimate body composition metrics from bioimpedance scale readings, providing context for your results.

lbs
%
inches

Fat Mass

39.6 lbs

Lean Mass140.4 lbs
Estimated Muscle Mass77.2 lbs
Estimated Body Water56.9 %

Fat Mass vs Body Weight

Understanding BIA (Bioelectrical Impedance Analysis)

BIA scales send a small electrical current through your body. Fat tissue conducts less electricity than lean tissue, allowing the device to estimate body composition.

From BIA Body Fat % We Can Derive

  • Fat Mass = Weight x Body Fat %
  • Lean Mass = Weight x (1 - Body Fat %)
  • Muscle Mass ~ Lean Mass x 0.55 (skeletal muscle is about 55% of lean mass)
  • Body Water ~ Lean Mass is about 73% water
  • Example Calculation

    A 180 lb male at 22% body fat per BIA scale.

    1. 01Fat mass = 180 x 0.22 = 39.6 lbs
    2. 02Lean mass = 180 x 0.78 = 140.4 lbs
    3. 03Est muscle = 140.4 x 0.55 = 77.2 lbs
    4. 04Est water = 0.78 x 73 = 56.9%

    Frequently Asked Questions

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