US Navy Body Fat Calculator
The Hodgdon–Beckett tape-measure method used by the US Navy — body fat from neck, waist (and hip) circumferences.
The Navy method was validated against hydrostatic weighing with a standard error around ±3.5% — excellent for a tape measure, but a real error bar. Measure at the same time of day, tape snug not compressing, and track the trend rather than any single reading.
Formula
For general information only — not medical or training advice. Estimates vary between individuals; consult a qualified professional before changing your exercise or nutrition routine.
The Hodgdon–Beckett tape-measure method used by the US Navy — body fat from neck, waist (and hip) circumferences. The US Navy Body Fat Calculator is a free, private navy body fat tool — every result computes instantly in your browser with no sign-up and no data upload.
About US Navy Body Fat Calculator
The Navy method was validated against hydrostatic weighing with a standard error around ±3.5% — excellent for a tape measure, but a real error bar. It applies M: 495 / (1.0324 − 0.19077·log₁₀(waist−neck) + 0.15456·log₁₀(height)) − 450. Use the US Navy Body Fat 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 US Navy Body Fat Calculator
- 1Enter your details in the US Navy Body Fat 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 US Navy Body Fat Calculator?
- ✓Instant navy body fat 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 (Hodgdon JA & Beckett MB, Naval Health Research Center Report 84-29 (1984))
- ✓Free forever with no sign-up, account or app install
Frequently asked questions
How does the US Navy Body Fat Calculator work?+
The Navy method was validated against hydrostatic weighing with a standard error around ±3.5% — excellent for a tape measure, but a real error bar. The calculation uses the formula: M: 495 / (1.0324 − 0.19077·log₁₀(waist−neck) + 0.15456·log₁₀(height)) − 450. Everything runs instantly in your browser as you type — your inputs are never uploaded.
Is the US Navy Body Fat Calculator accurate, and what is it based on?+
The method is traceable to authoritative sources, including Hodgdon JA & Beckett MB, Naval Health Research Center Report 84-29 (1984); ACE — body-fat percentage norms. Results are estimates — individual variation always applies, so treat the output as a well-grounded starting point.
Is the US Navy Body Fat 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 fitness information only, not medical or training advice. Consult a professional before changing your routine.
What can I use the US Navy Body Fat Calculator for?+
It's commonly used for navy body fat, tape test, circumference body fat. The Hodgdon–Beckett tape-measure method used by the US Navy — body fat from neck, waist (and hip) circumferences.
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