FFMI Calculator Icon

FFMI Calculator

Calculate Fat-Free Mass Index with the FFMI Calculator

Fat-Free Mass Index Chart

Calculate your fat free mass index using the FFMI calculator above and compare your results against the FFMI chart below. The values in this chart apply to both genders.

FFMI Range Description
Underweight < 18
Average 18 - 20
Above Average 20 - 22
Excellent 22 - 23
Peak Fitness 23 - 26
Extreme Levels 26 - 28
Steroid Use Likely > 28

Share this page

What is Fat-Free Mass Index?

The Fat-Free Mass Index (FFMI) is a measurement of body fat percentage in comparison to your entire body weight. Calculating your FFMI is important because it provides early indications of health risks.

An individual with a higher percentage of body fat has a greater risk of developing heart disease, stroke and other serious illnesses than someone with a higher fat-free mass index score.

How to Measure Fat-Free Mass Index

To measure your fat-free mass index, follow these 3 simple steps:

  1. Measure your height in centimeters.
  2. Measure your weight in kilograms.
  3. Measure your body fat percentage.
  4. Enter details in the FFMI Calculator.

You will instantly get your FFMI score as the result of this calculation.

Why Measure FFMI?

Determining whether you are at a healthy weight is important for many reasons. The most common method for doing this is to step on a scale, but if you are looking for something a little more accurate, then Fat-Free Mass Index (FFMI) might be a better alternative for you.

This measurement essentially calculates your body fat as a percentage of your overall weight. It's not perfect, but it's gaining in popularity as people realize that it's a more accurate reflection of body composition than BMI.

Is FFMI Better than BMI?

The accuracy of BMI has been called into question on several occasions in recent years, with some experts claiming that it is no longer a reliable measure of health. For this reason, researchers have been trying to find better ways to measure health.

There are a few reasons why alternative health tests like the FFMI Calculator and the RFM Calculator are seen as a more accurate measure than BMI:

  • BMI doesn't account for different body types
  • BMI does not take into account how much of a person's weight is muscle
  • BMI does not always give an accurate picture of someone's health

Because of these limitations, it is possible for BMI to give an inaccurate picture of your health.

For example: a person who is very muscular may still have a high BMI but a low FFMI. This is because BMI does not take into account visceral fat, which is the type of fat that is most harmful to health.

What is the Fat-Free Mass Index?

The Fat-Free Mass Index (FFMI) is a measure of body composition that takes into account both muscle mass and body fat. It is calculated by dividing one's fat-free mass (FFM) by their height squared. FFMI was created to compare people of different body compositions.

The average FFMI for male athletes is 25, while the average for female athletes is 21.5. Some people, including bodybuilders, have been known to reach an FFMI of 30.5, which is considered the upper bound for natural athletes. It takes extreme work and dedication to reach this level.

The FFMI calculator is a useful tool for athletes and bodybuilders to track their progress and ensure that they are staying within a healthy range.

What is the Fat-Free Mass Index Formula?

The fat-free mass index formula (or FFMI formula) varies based on gender. You can calculate relative fat mass percentage using the following formula:

Fat-Free Mass Formula:
Fat Free Mass = weight [kg] * (1 - (body fat [%]/ 100))
FFMI Formula for Men/Women:
FFMI = fat free mass [kg]/ (height [m])²

What is the Average Body Fat Percentage?

The percentage of body fat we have varies depending on our age and gender. Women, on average, have more body fat than men.

The CDC's study from 1999-2004 shows that, on average, men have a higher body fat percentage than women (see chart below).

  • Men have an average body fat percentage of 24% to 30%
  • Women have an average body fat percentage of 32% to 42%
Average body fat percentage by age and gender
Source US Government official site - CDC, (Wikipedia)