Formula
WHtR = waist circumference ÷ height (same units) How it works
Waist-to-height ratio compares the size of your waist with your height. Fat stored around the abdomen, particularly around the organs, is more closely linked to type 2 diabetes, high blood pressure and heart disease than fat elsewhere, and this ratio captures it in a way BMI does not.
The guiding message is simple: keep your waist to less than half your height. A ratio under 0.5 is generally considered healthy for adults of any sex and most ethnic backgrounds; 0.5–0.59 indicates increased risk and 0.6 or more high risk. The UK’s NICE guidance recommends using it alongside BMI.
Measure on bare skin after breathing out normally, with the tape level all the way around and not pulling in. Units do not matter as long as waist and height use the same one. This is a screening measure, not a diagnosis or medical advice.
Frequently asked questions
Is waist-to-height ratio better than BMI?
Several studies find it predicts cardiometabolic risk at least as well as BMI, and it flags people with a "normal" BMI but excess belly fat. Using both together gives the best picture.
Does it work for children?
The 0.5 cut-off is often used for children over 5 as well, though pediatric assessment normally relies on growth charts.