Input Parameters
Real-time calculation updates dynamically as you adjust inputs. Values remain strictly local on your device.
Body Fat PercentageFitness
16.2%
ACE Category: Fitness
Fat Mass
12.1kg
Lean Body Mass
62.9kg
Fat-Free Mass Index
20.8kg/m²
Clinical Responsibility Note: This calculation provides statistical estimations for informational and educational purposes only. It is not an individualized medical diagnosis or clinical prescription.
Mathematical Formula & Scientific Methodology
Formula: US Navy Circumference Equation
Men: 495 / [1.0324 - 0.19077·log10(waist-neck) + 0.15456·log10(height)] - 450Empirical logarithmic model calibrated against hydrostatic underwater weighing in military personnel.
Model Assumptions
- Standard tape measure tension without compressing soft tissue
Variables & Standard Units
| Symbol | Physiological Meaning | Unit |
|---|---|---|
| waist | Abdominal circumference at navel | cm |
| neck | Neck circumference below larynx | cm |
| height | Standing stature | cm |
Scientific Limitations
- Typical margin of error ±3% compared to dual-energy X-ray absorptiometry (DEXA)
Peer-Reviewed Scientific Citations
Relative fat mass (RFM) as a new estimator of whole-body fat percentage - A cross-sectional study in American adult individuals (2018)
Woolcott OO, Bergman RN (2018) — Scientific Reports, 8, 10980
Key Finding: RFM = 64 - (20 * height / waist) + (12 * sex). Validated against DEXA with higher diagnostic accuracy for body fat percentage than BMI.
Frequently Asked Questions
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