Estimate body fat percentage from height and waist circumference using the Relative Fat Mass (RFM) method.
How It Works
How Relative Fat Mass Calculator Works
RFM is a newer body fat estimation method built purely from a height-to-waist ratio, with separate baseline constants for men and women — several recent studies have found it correlates with actual measured body fat at least as well as BMI does, while needing only a tape measure rather than a scale.
FAQ
Frequently Asked Questions
Why does the formula only need waist and height, not weight?
Waist circumference tends to track abdominal fat closely, and the RFM formula was statistically derived to approximate body fat percentage from that single measurement relative to height, without needing weight in the equation at all.
Why are the men's and women's formulas different?
Men and women carry and distribute body fat differently on average, so the formula uses separate baseline constants (64 for men, 76 for women) calibrated against each group's typical body composition.
