FFMI Calculator (Fat-Free Mass Index)

Calculate your Fat-Free Mass Index — a measure of muscularity relative to height that helps assess if a physique is naturally achievable.

💪 FFMI Calculator

Weight (kg)

Height (cm)

Body Fat (%)

Results

FFMI22.2

Normalized FFMI22.5

Lean Body Mass68.0 kg

Fat Mass12.0 kg

CategoryExcellent

💡 What Is FFMI?

FFMI = lean body mass (kg) / height (m)². The normalized FFMI adjusts for height differences: NFFMI = FFMI + 6.1 × (1.8 − height in m). This allows fair comparison between people of different heights.

A landmark 1995 study found that natural bodybuilders rarely exceed a normalized FFMI of 25. Steroid users averaged 25+. An FFMI of 22-23 represents an excellent natural physique.

80 kg, 175 cm, 15% body fat: LBM = 68 kg. FFMI = 22.2, Normalized FFMI = 22.5 (Above Average — excellent natural physique).