Fat Free Mass Index Calculator
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 Fat Free Mass Index Calculator calculator will help you to find your FFMI using your body fat.
Calculate Fat-Free Mass Index
Fat Free Mass Index Formula
Lean = Weight * ( 1.0 – (BodyFat / 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
Fat Free Mass Index Normal Range
The following table introduces the FFMI scores and their interpretation in terms of muscle mass:
FFMI score | Muscle mass interpretation |
16 – 17 | Below average |
18 – 19 | Average |
20 – 21 | Above average |
22 | Excellent |
23 -25 | Superior |
26 – 27 | Suspicion of steroid use* |
28 – 30 | Steroid usage likely** |