Relative Fat Mass (RFM) Calculator

This on-line RFM calculator takes your height and waist circumference and calculates the Relative Fat Mass in the body. This calculator is only for adults of age 20 and above. Just like BFP calculator, this calculator will also give an approximate result.

Using the RFM calculator

1. Select your Gender.
2. Enter your Height either in centimeters or in feet.
3. Enter the Waist circumference either in inches (in) or centimeters (cm). (See guidelines below for taking measurement.)
4. Then, click the Calculate RFM button. The relative fat mass of the body will be calculated and the result will be displayed in the box below the button.

Guide For Measuring Waist Circumference

1. Wear little cloth as possible.
2. Stand straight with your feet close together.
3. Keep your arms down at the sides.
4. Take the measurement after the end of a normal expiration.
5. For Male: Measure the circumference of waist across the belly button. Repeat the measurements twice and take the average.
   For Female: Measure the smallest circumference of the waist, (The smallest circumference is usually halfway between the lower point of sternum and the belly button) roughly one inch above the belly button. Repeat the measurements few times and take the smallest value.

Relative Fat Mass (RFM) is another estimator for calculating the percentage of fat in the human body. This was put forward by Orison O. Woolcott & Richard N. Bergman in a study (Relative fat mass (RFM) as a new estimator of whole-body fat percentage ─ A cross-sectional study in American adult individuals). RFM is not as popular as Body Fat Percentage (BFP). However, accuracy of RFM is claimed to be higher than BFP for adult men and women.

Formula

There are separate formulas for men and women to calculate the Relative Fat Mass. Let's see them.

Relative Fat Mass Formula for Men

RFM for Men = 64 − (20 × (Height ÷ Waist) )

Where:

• Height in meters.
• Waist circumference in meters.

Relative Fat Mass Formula for Women

RFM for Women = 76 − (20 × (Height ÷ Waist) )

Where:

• Height in meters.
• Waist circumference in meters.

Common Formula

The above individual formulas for men and women can be combined like this.

RFM = 64 − (20 × (Height ÷ Waist) ) + (12 × Sex)

Where:

• Sex = 0 for men and 1 for women.
• Height in meters.
• Waist circumference in meters.

Fat Percent Category

• Relative fat mass (RFM) as a new estimator of whole-body fat percentage ─ A cross-sectional study in American adult individuals by Orison O. Woolcott & Richard N. Bergman.