Health Logo. FFMI Calculator

Fat Free Mass Index Calculator.

FFMI is an alternative to body mass index which accounts for a person's muscle mass. The average male scores about 19 and it is hard to score above 25 without using steroids or other banned substances.

Imperial

Height feet inches
Weight pounds
Body fat %

Fat-free mass pounds
FFMI
Normalized FFMI

Metric

Weight kilos
Height meters
Body fat %

Fat-free mass kilos
FFMI
Normalized FFMI

Mathematical Formulas

  • Lean Weight = Weight * (1 - (body fat % / 100)
  • FFMI = (Lean Weight / 2.2)/ ((Feet * 12.0 + Inches) * 0.0254)2
  • Adjusted FFMI = FFMI + ( 6.3 * (1.8 - (Feet * 12.0 + Inches) * 0.0254))

See also: Fat-free mass index in users and nonusers of anabolic-androgenic steroids.