Adjusted FFMI Calculator 

This Fat Free Mass Index (FFMI) calculator estimates fat-free body mass by including your body fat percentage to deduce your lean body mass expressing a value implying overall muscularity.

Calculate your Fat Free Mass Index or FFMI.

Calculate Adjusted FFMI

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Weight:   lbs
Bodyfat:   %
Height:  ft. in.
Lean:   lbs
Adjusted FFMI: 

Adjusted FFMI values under 19 indicates low muscle mass, scores 19-20 express normal muscle mass, scores 21-24 suggest above average muscle mass, and values above 25 imply unnatural chemically enhanced muscularity by use of anabolic steroids[1]. Unlike the BMI calculator that estimates body mass index by height and weight measurements, the Fat Free Mass Index (FFMI) calculator above calculates your fat-free body mass value by including your body fat percentage to deduce lean body mass over gross body mass. Athletes, bodybuilders, fitness and sport enthusiasts require more accurate metrics and tools to estimate fat-free mass index because these populations of people typically hold lower body fat and higher muscle mass percentages.

[1] Kouri EM, Pope HG Jr, Katz DL, Oliva P. Clinical Journal of Sports Medicine. Fat-free mass index in users and nonusers of anabolic-androgenic steroids. 1995 Oct;5(4):223-8. [PubMed]

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calculators was last modified: December 14th, 2018 by Derek Curtice