Health Calculators
FFMI Calculator (Fat-Free Mass Index)
Compute fat-free mass index (FFMI), normalized FFMI, lean mass, and total body fat from height, weight, and body fat percentage.
Enter sex, height, weight, and body fat percentage. The calculator uses the standard FFMI formulas: fat-free mass = weight × (1 − body fat %/100), FFMI = fat-free mass / height², normalized FFMI = FFMI + 6.1 × (1.8 − height in m).
Results can be shown with the same mass unit dropdown (g, dag, kg, lb) on each output; FFMI and normalized FFMI show the mass-style unit with a /m² suffix, FFMI widget.
Sex
Height
cm
Weight
kg
Body fat
%
FFMI
kg/m²
Normalized FFMI
kg/m²
Fat-free mass
kg
Total body fat
kg
Think you really understand your muscle-to-fat balance?and see if your knowledge is as strong as your training. 💪