Fat-Free Mass Index


FFMI is an alternative to BMI where in FFMI, the muscle along with fat mass is considered based on height and weight. But the muscle mass is not taken into consideration in BMI. This online FFMI calculator will help you to find your FFMI using your body fat.

Fat Free Mass Index Calculator

kg
lbs
%
cm
feet
inches

Formula for Fat Free Mass Index

Lean = Weight * ( 1.0 – (Body Fat / 100.0 ))
FFMI = ( Lean / 2.2 ) / ((Height * 12.0 + Inches) * 0.0254)2
Adjusted FFMI = FFMI + ( 6.0 * ( ((Height * 12.0 + Inches) * 0.0254) – 1.8 ))

Fat free mass index is useful for athlete people who has muscle rich body.

Example

A person weighing 50 kgs, with body 12 % and height 5’4 will have

Lean Weight =

=50 * (1.0 – (12 / 100))
= 50 * ( 1 – 0.12)
= 50 * 0.88
= 44.00 kg

FFMI

 = ( 44 / 2.2) / ((5*12.0) + 4)*0.0254)^2
= 20 / ((60 + 4) * 0.0254)^2
= 20 / (1.6256)^2
= 20 / 2.6425
= 7.56

Adjusted FFMI

 = FFMI + (6* 5 + 12.0 + 4) * 0.0254) – 1.8
= 7.56 + ( 6.0 * ( ((5 * 12.0 + 4) * 0.0254) – 1.8 ))
= 6.522