Neck-to-Height Ratio Calculator

About this calculator

Neck-to-height ratio simply divides neck circumference by height and expresses it as a percentage, offering a single-tape-measure alternative to full body-composition testing. It builds on the same logic as neck-circumference screening used in sleep-medicine questionnaires (like the Berlin and STOP-Bang tools, where a neck over roughly 40 cm/17 in flags higher obstructive sleep apnea risk), since upper-body fat tends to collect around the neck as well as the abdomen.

Because the ratio scales neck size to a person's height rather than using a fixed cutoff, it is sometimes used informally as a quick proxy for central adiposity or general body composition trends over time. It is not a diagnostic tool and doesn't replace BMI, waist-to-height ratio or clinical body-fat measurement — it is best read as one more simple, low-cost signal alongside those other measures.