Body-Fat Estimate (Relative Fat Mass)
Estimate body-fat percentage from height and waist using the published Relative Fat Mass equation.
What this answers:
- Using height and waist circumference, what does the RFM equation estimate for body-fat percentage?
This is an anthropometric estimate, not a measured body-composition result (such as from a DEXA scan), and this tool does not assign diagnostic categories to the number. Measure your waist at the same landmark used in the published protocol (typically at the navel, standing, relaxed) for a meaningful result. Adults age 20+ only.
Estimated body fat
-
How it's calculated
RFM% = 64 − 20 × (height/waist) + 12 × sex (sex = 0 male coefficient, 1 female coefficient)
Worked example
Height 180 cm, waist 90 cm: 24% (male coefficient) or 36% (female coefficient).
Source: Woolcott & Bergman, Relative fat mass as a new estimator of whole-body fat percentage, Scientific Reports 2018. Source last checked September 28, 2026.
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