Calculating your FMI

The fat mass index allows you to evaluate the proportion of fat in the body

Definition of FMI

Are you wondering what is the fat mass index? Would you like to know how to find out your fat mass index? It’s actually very easy, because the calculation is based on your weight, height, age and your gender.

Here’s the formula used to calculate your FMI:

  • FMI in % = (1.2 x your BMI) + (0.23 x your age) - (10.8 x your gender (female = 0, male =1)) - 5.4

The FMI shows the proportion of fat in your body.

The ideal fat mass index

The ideal fat mass index for women is between 25 and 30%.

  • FMI lower than 25%: the person is too thin
  • FMI between 25% and 30% inclusive: the person is normal
  • FMI above 30%: the person has too much fat

The ideal fat mass index for men is between 15 and 20%

  • FMI lower than 15%: the person is too thin
  • FMI between 15% and 20% inclusive: the person is normal
  • FMI above 20%: the person has too much fat