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Body-Fat Percentage (Navy Circumference Method)

The percentage of your weight that is fat. The U.S. Navy circumference method estimates it from height, neck, waist, and hip measurements — the same approach used in many service assessments.

Educational reference only. The numbers on this page summarize public service regulations for planning purposes. They are not official medical, recruiting, or administrative determinations. Always confirm your status with a recruiter, commanding officer, or hiring agency using the official assessment.

Formula

Navy method: Men: 495 ÷ (1.0324 − 0.19077·log10(waist−neck) + 0.15456·log10(height)) − 450 · Women: 495 ÷ (1.29579 − 0.35004·log10(waist+hip−neck) + 0.22100·log10(height)) − 450

Healthy range

Athletes 6–13% (men) / 14–20% (women); healthy 14–24% (men) / 21–33% (women). Military limits depend on branch, sex, and age (e.g., Army 17–20: 20% men / 30% women, rising with age).

Military & first-responder angle

Body-fat % is the secondary evaluation when a service member fails the WHtR screen. DoD Instruction 1308.03 sets the corridor: no branch stricter than 18% (men) / 26% (women), none looser than 26% / 36%.

Calculator

Estimate body-fat % with the exact U.S. Navy circumference formula (neck + waist; hips for women).

Result

Estimated body-fat %17.5%
±3–4% versus DXA. Women must include hip. This is the Navy method used as a cross-branch estimate; your service runs its own official assessment.

Quick answers

What is the Navy circumference method?
A tape-measure formula (neck, waist, and for women hip) that estimates body-fat percentage without calipers or scans. Many branches use it for the secondary body-fat evaluation.
How accurate is it?
Within roughly ±3% of DXA for most people when measured carefully. DXA, Bod Pod, and InBody are more accurate and can be requested as supplemental assessments under AR 600-9.
Do firefighters or police have a body-fat limit?
No federal body-fat standard for either. Firefighter readiness uses the CPAT and NFPA 1580 fitness testing; law enforcement uses state POST agility tests.

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