Waist To Height Ratio
Calculator

You divide your waist circumference by your height, using the same units for both, to get a ratio that indicates how much abdominal fat you carry relative to your body size. It's used as a quick screening tool for cardiometabolic risk, since abdominal fat is more strongly linked to health risk than fat elsewhere.

A commonly cited guideline is to keep your waist circumference below half your height, meaning a ratio under 0.5, with higher values associated with increased risk of conditions like type 2 diabetes and heart disease. This threshold is intended to apply fairly consistently across different heights, unlike some other measures.

Waist-to-height ratio directly captures central fat distribution, which BMI cannot, since two people with the same BMI can have very different amounts of abdominal fat. Several studies have found it to be a comparable or better predictor of cardiometabolic risk than BMI alone.

The standard technique measures around the narrowest part of your torso, typically at the level of your belly button or the midpoint between your lowest rib and the top of your hip bone, taken after exhaling normally without pulling the tape tight. Measuring at an inconsistent location from one time to the next will produce misleading trend data.

The 0.5 threshold has shown reasonable validity across a wide age range including children, which is part of its appeal compared to BMI, which requires different percentile charts for kids. That said, this calculator is generally intended for adult use, and pediatric assessments should involve a pediatrician.