Waist-to-Height Ratio Calculator
A one-number check for central-fat risk. Studies (Ashwell 2012, NHS) find WHtR predicts cardiometabolic risk better than BMI — and the rule is simple: keep your waist under half your height.
How waist-to-height ratio works
Waist-to-height ratio (WHtR) divides your waist circumference by your height, in the same units. It flags visceral fat — the fat wrapped around your organs — which is the type most strongly linked to type-2 diabetes, high blood pressure, and heart disease.
Ashwell / NHS thresholds:
Very slim
Healthy
Increased
High risk
How to measure your waist
Stand relaxed, exhale, and wrap a tape measure horizontally around your natural waistline — roughly halfway between the bottom of your ribs and the top of your hip bones. Don't suck in. Belt size is a close approximation if you don't have a tape.
Want a full healthy weight range too? Try the Quick Target Weight calculator. Also check your body frame size to see how bone structure adjusts your target range.
Frequently asked questions
What is a healthy waist-to-height ratio?
Under 0.50 is considered healthy for most adults. Below 0.40 is very slim, 0.40-0.50 is healthy, 0.50-0.60 signals increased risk, and above 0.60 is high risk.
Is WHtR better than BMI?
Research by Ashwell and the NHS suggests WHtR is a better predictor of heart disease, diabetes, and overall mortality risk than BMI because it specifically measures dangerous abdominal fat.
How do I measure my waist correctly?
Stand relaxed, exhale, and wrap a tape measure horizontally around your natural waistline, about halfway between your ribs and hip bones. Don't pull in your stomach.
What should I do if my ratio is over 0.50?
A ratio over 0.50 suggests increased central fat. Focus on waist-reducing habits such as reducing refined carbohydrates, increasing protein and fiber, and adding regular strength training and walking. For personalized advice, speak with a healthcare provider.