Normalized FFMI Calculator

Calculate your Normalized Fat-Free Mass Index—the gold standard for evaluating natural muscle development potential, scientifically adjusted for height.

Don't know yours? Use a DEXA scan, calipers, or a visual guide estimate.

About Normalized FFMI

FFMI = Lean Body Mass (kg) ÷ Height² (m²). Unlike BMI, it measures your muscle mass relative to your height.

Normalized FFMI adjusts for height differences by scaling all values to a reference height of 1.80m, allowing fair comparisons across body sizes. A landmark 1995 study by Kouri et al. found that natural bodybuilders rarely exceeded a Normalized FFMI of 25. Values above 26 are rare drug-free and are considered a marker of potential performance enhancement.

⚡ Also Try

Use our BMI Calculator → for a general health screening metric.