RFM Calculator
Calculate your Relative Fat Mass (RFM) using just height and waist circumference. RFM provides a body fat estimate that correlates well with DEXA scan results.
Measure at the narrowest point, usually at the navel level
📊 Interpretation
--
Understanding RFM
Relative Fat Mass (RFM) was developed in 2018 as a simple, accurate alternative to BMI for estimating whole-body fat percentage. It uses only height and waist circumference and shows strong correlation with DEXA scan measurements.
RFM = 76 − (20 × 165/75) + 12 = 76 − 44 + 12 = 44%
Example (Male): Height = 180 cm, Waist = 90 cm
RFM = 64 − (20 × 180/90) + 0 = 64 − 40 = 24%
📏 How to Measure Waist Circumference
- Stand relaxed with feet together
- Find your natural waist (narrowest point between ribs and hips)
- Alternatively, measure at navel level
- Wrap tape horizontally, keeping it snug but not tight
- Measure after exhaling normally
Frequently Asked Questions
Relative Fat Mass is a body fat estimation formula using height and waist circumference. It was developed in 2018 and validated against DEXA scans.
RFM estimates body fat directly rather than just weight-to-height ratio. Studies show it correlates better with DEXA-measured body fat than BMI does.
Women naturally have higher essential body fat (for reproduction) than men. The formula adds 12 for females to account for this biological difference.
Measure at your natural waist (narrowest point) or at navel level. Be consistent if tracking over time.