Relative Fat Mass – RFM Calculator

RFM Calculator is a tool which estimates your body fat percentage based on your height and waist measurements.

Relative Fat Mass (RFM) Calculator

RFM Calculator

Relative Fat Mass (RFM) Definition and RFM Formula

Relative Fat Mass (RFM) is a relatively new approach to estimate body fat percentage. The goal of RFM is to offer a simpler, yet similarly effective method compared to other body fat percentage calculations such as Body Mass Index (BMI). Instead of relying on complex and sometimes invasive measurements, RFM uses only height and waist circumference. The advantage is that these values are easy to measure and enable you to enter directly into the formula when measured.

The formula for RFM is different for men and women:

For men:

\text{RFM} = 64 - (20 \times \frac{\text{height}}{\text{waist circumference}})

For women:

\text{RFM} = 76 - (20 \times \frac{\text{height}}{\text{waist circumference}})

Height and waist circumference are both calculated in meters in this formula.

How to calculate Relative Fat Mass (RFM) using this calculator

The RFM calculator does not require high-level healthcare information and is designed for an ordinary person to use it easily. Its provides users a quick and reliable estimation of their body fat percentage based on just two measurements: height and waist circumference.

Step 1: Measure Your Height To get an accurate RFM value, it’s essential to measure your height correctly.

  1. Stand straight against a wall without shoes.
  2. Make a mark on the wall level with the top of your head.
  3. Use a measuring tape to measure from the floor to the mark.
  4. Record the height in meters or centimeters. (You can convert feet and inches to meters using this conversion tool).

Step 2: Measure Your Waist Circumference Waist circumference gives an indication of visceral fat around the organs, a key component in RFM.

  1. Stand and wrap a tape measure around your waist at the level of your belly button.
  2. Ensure the tape is snug but not too tight and that it is parallel to the floor.
  3. Breathe out naturally before taking the measurement.
  4. Record the circumference in centimeters or meters.

Step 3: Input Measurements into the Calculator Once you have both values, input your height and waist measurement into the respective fields in the calculator. Ensure you select the appropriate gender as the formula differs slightly between men and women.

Step 4: Get Your RFM Value After inputting your measurements, the calculator will automatically provide your RFM value.


How does RFM compare to BMI?

While both RFM and BMI (Body Mass Index) are tools used to analyze body composition, they measure different things. BMI only considers weight and height and does not distinguish between muscle and fat. RFM, on the other hand, specifically estimates body fat percentage using height and waist circumference. Some healthcare professionals believe that RFM can provide a more accurate representation of body fat in various populations than BMI. You can check more about the comparison between RFM and BMI here.

Does RFM show how healthy I am?

No single measurement can definitively assess overall health. While RFM provides insights into body fat composition, it’s recommended to consult healthcare professionals and consider other factors like diet, exercise etc. when evaluating health.