Skip to main content
aifithub

Reference · 42 cells

Body Fat by Waist and Neck Circumference

This table shows the U.S. Navy method body-fat estimate for a male at 180 cm across waist (72–108 cm) and neck (34–44 cm) circumference. For example, a 90 cm waist with a 38 cm neck estimates 19.8% — the “Average” range.

Every value below is computed live from the Body Fat calculator engine. Read the methodology for the circumference formula, how to measure at home, or the lean-mass decision tree.

Download CSV (42 rows) CC BY 4.0 · free to cite

Body-fat grid: waist rows × neck columns

U.S. Navy body fat (%), male, 180 cm · rows = waist (cm) · columns = neck (cm)
Waist \ Neck 343638404244
72 8.56.64.62.50.3-2
78 13.712.110.38.56.64.6
84 18.416.915.313.712.110.3
90 22.621.219.818.416.915.3
96 26.425.223.922.621.219.8
102 29.928.827.626.425.223.9
108 33.232.131.129.928.827.6

Cells are estimated body-fat percentage by the U.S. Navy circumference method. A larger waist raises the estimate; a thicker neck lowers it (the neck stands in for lean upper-body mass). Height is fixed at 180 cm.

Provenance

Engine
Body Fat Percentage Calculator (body-fat-percentage-calculator)
Source
Computed live from /engines/body-fat-percentage-calculator.js
Axis A (rows)
Waist: 72, 78, 84, 90, 96, 102, 108 cm
Axis B (columns)
Neck: 34, 36, 38, 40, 42, 44 cm
Fixed inputs
sex = male, height = 180 cm
Grid size
7 × 6 = 42 cells
Headline metric
body fat (%) — U.S. Navy method
Last computed
2026-05-23

Generation note: the engine is deterministic — no wall-clock, no randomness — so each cell reproduces exactly on every build. The full grid is embedded as machine-readable JSON and recomputed by our CI gate against a fresh engine run; the table and CSV are rendered from those same outputs, never hand-entered.

Run your own numbers

General fitness estimates — not medical advice. Consult a healthcare professional for medical decisions.