Formula
Waist-to-height ratio = waist ÷ height (same units)
Example: a waist of 80 cm and height of 165 cm gives 80 ÷ 165 = 0.48, which is in the healthy range.
Waist-to-height ratio chart
| Ratio | What it means |
|---|---|
| Below 0.4 | Low – make sure you are not underweight |
| 0.4 – 0.49 | Healthy |
| 0.5 – 0.59 | Increased health risk |
| 0.6 or more | High health risk |
Why it works well
Unlike BMI, waist-to-height ratio looks at belly fat directly and adjusts for height. A large review found it predicted heart and diabetes risk better than BMI or waist size alone, and UK health guidelines added it in 2022.
Frequently asked questions
What is a healthy waist size for my height?
Divide your height by two. For 170 cm, keep your waist under 85 cm (about 33.5 inches).
Is waist-to-height ratio better than BMI?
It is better at spotting belly fat, which drives most health risk. Using both gives the best picture.
Sources
- National Institute for Health and Care Excellence (NICE). Obesity guideline update on waist-to-height ratio, 2022.
- Ashwell M, Gunn P, Gibson S. Waist-to-height ratio is a better screening tool than waist circumference and BMI for adult cardiometabolic risk factors: systematic review and meta-analysis. Obesity Reviews, 2012.
Medical disclaimer: This calculator gives estimates for general information only. It is not a diagnosis or a substitute for advice from a doctor or registered dietitian. Please consult a healthcare professional before making changes to your diet, exercise or medicines, especially if you are pregnant, have a medical condition or take regular medication.
Last updated: 20 October 2026. Read our editorial policy.
