Convert Neck measurement
Typical range: 37–44 cm for adult men, 32–38 cm for adult women
How to measure
Stand looking straight ahead with shoulders relaxed and not hunched. Place a flexible tape measure around the neck just below the larynx (Adam's apple in men), with the tape level all the way around. The tape should sit horizontally — not sloping up at the back. Apply only enough tension to keep the tape in place without compressing soft tissue.
Tips for accuracy
- Don't tilt the head up or down — look straight ahead
- Measure just below the Adam's apple in men; at the narrowest point in women
- Don't pull the tape tight; just enough to maintain contact with skin
- Neck > 43 cm (17 in) in men correlates with elevated sleep apnea risk
Common mistakes
- Chin tilt — tilting the chin up or down changes neck girth noticeably; keep the head level, looking straight ahead, not up or down
- Tape angle following the jaw — the tape should sit level all the way around, perpendicular to the neck's long axis, not angled to follow the jawline, which inflates the reading
- Talking or swallowing mid-measurement — both visibly move the neck muscles and can shift the tape; hold still and breathe normally during the actual reading
- Measuring over a collar — even a t-shirt collar can add enough bulk to matter for a measurement this size-sensitive
What affects this measurement
Neck circumference has comparatively little muscle-mass variation in most people compared to sites like the bicep or thigh — which is precisely why the Navy body fat formula uses it as a stable reference point alongside waist (and hip, for women): a change in neck girth over time is more likely to reflect fat gain or loss than muscle growth for the average person, unlike a site such as the bicep where both explanations are equally plausible.
What it's used for
A required input for the US Navy body fat calculator, and the McCallum ideal-proportions calculator.
Sources & standards
Measurement technique on this page follows standardized anthropometric protocol — CDC/NHANES for the general circumference-measurement standard used in clinical and population research, and ACE for fitness-industry assessment guidance. Bodybuilding-specific reference ranges (e.g. “typical for trained athletes”) are general guidance, not a clinical benchmark — individual results vary by frame size, training history, and genetics.