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EncyclopediaRelative Fat Mass (RFM)
A Biometric Story
Often called: RFM, Modern Fat Estimate

Relative Fat Mass (RFM)

A smart way to estimate your body fat using just a tape measure.

The Science of You

RFM is like a more advanced version of BMI. It uses a clever formula that considers your height and waist to guess how much of your body is fat versus muscle. It's famous for being remarkably close to medical-grade scans without needing $1,000 equipment.

Why it Matters for You

Knowing your RFM helps you understand your body composition. It's a great motivator to see this number drop as you incorporate more joyful movement and nourishing foods into your life.

Active & Lean (M)
2 – 13%
Balanced Lifestyle (M)
14 – 24%
Health Reset Focus
25%+

Calculate Metrics

Relative Fat Mass (RFM)

A simpler, clinical alternative to BMI.

Body Fat Calculator

Estimate body fat percentage via US Navy method.

Quick Definitions

Body Mass Index (BMI)Resting Heart Rate (RHR)Waist-to-Height Ratio (WtHR)Lean Body Mass (LBM)Biological AgeBasal Metabolic Rate (BMR)Heart Rate Variability (HRV)VO2 MaxGrip StrengthMacronutrients (Macros)Visceral FatBlood GlucoseCholesterol RatioSleep EfficiencyHydration StatusWalking SpeedBone ResiliencePhase AngleLung VitalityBody Water %Recovery Window

Health Audit

Get all your biometric metrics in a single clinical report.

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