Relative Fat Mass (RFM) Calculator
The 2018 two-measurement formula (height ÷ waist) that tracked DXA scans better than BMI in 12,000 adults.
Woolcott and Bergman screened 365 candidate anthropometric formulas against DXA in NHANES data; this two-variable winner needs no weight at all. It estimates whole-body fat percentage with less sex/ethnicity bias than BMI, though like all tape methods it can't see where fat sits.
Formula
For general information only — not medical advice, a diagnosis or a treatment plan. Consult a qualified healthcare professional before making health, diet, medication or exercise decisions.
The 2018 two-measurement formula (height ÷ waist) that tracked DXA scans better than BMI in 12,000 adults. The Relative Fat Mass (RFM) Calculator is a free, private relative fat mass tool — every result computes instantly in your browser with no sign-up and no data upload.
About Relative Fat Mass (RFM) Calculator
Woolcott and Bergman screened 365 candidate anthropometric formulas against DXA in NHANES data; this two-variable winner needs no weight at all. It applies RFM = 64 − 20 × (height ÷ waist) (men) · 76 − 20 × (height ÷ waist) (women). Use the Relative Fat Mass (RFM) Calculator to get an instant, clearly-explained result with the working shown step by step — free, private and with the source method cited.
How to use Relative Fat Mass (RFM) Calculator
- 1Enter your details in the Relative Fat Mass (RFM) Calculator input fields above.
- 2The result updates instantly with the working and reference bands shown.
- 3Adjust any value to explore how it changes the outcome — it's free and unlimited.
Why use Relative Fat Mass (RFM) Calculator?
- ✓Instant relative fat mass result that recomputes as you type — no waiting, no page reloads
- ✓100% client-side: your health data never leaves your browser
- ✓Shows the actual formula and your numbers substituted in, so you can see exactly how the result is reached
- ✓Based on published, citable sources (Woolcott OO & Bergman RN, Sci Rep 2018;8:10980)
- ✓Free forever with no sign-up, account or app install
Frequently asked questions
How does the Relative Fat Mass (RFM) Calculator work?+
Woolcott and Bergman screened 365 candidate anthropometric formulas against DXA in NHANES data; this two-variable winner needs no weight at all. The calculation uses the formula: RFM = 64 − 20 × (height ÷ waist) (men) · 76 − 20 × (height ÷ waist) (women). Everything runs instantly in your browser as you type — your inputs are never uploaded.
Is the Relative Fat Mass (RFM) Calculator accurate, and what is it based on?+
The method is traceable to authoritative sources: Woolcott OO & Bergman RN, Sci Rep 2018;8:10980. Results are estimates — individual variation always applies, so treat the output as a well-grounded starting point.
Is the Relative Fat Mass (RFM) Calculator free and private?+
Yes. It's completely free with no sign-up, and all computation happens locally in your browser, so none of your health data ever leaves your device.
Can I use this for medical decisions?+
This tool is for general information only and is not medical advice. Always consult a qualified healthcare professional before making health decisions.
What can I use the Relative Fat Mass (RFM) Calculator for?+
It's commonly used for relative fat mass, rfm calculator, bmi alternative. The 2018 two-measurement formula (height ÷ waist) that tracked DXA scans better than BMI in 12,000 adults.
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