How to use it
- Choose your Sex, because the WHO limits differ.
- Measure your Waist and Hips in centimetres and enter them, then enter your Height.
- Read the Waist-hip ratio against the WHO limit, then the Waist-to-height ratio against 0.5.
How the ratios are calculated
The waist-hip ratio is the waist measurement divided by the hip measurement, both in the same unit. The World Health Organization treats abdominal obesity, a raised risk, as a ratio above 0.90 in men and above 0.85 in women. Those cut-offs come from a WHO expert consultation held in Geneva in 2008 and published in 2011.
The waist-to-height ratio is the waist divided by the height. A boundary value of 0.5 has been proposed to show increased risk, in a review by Browning, Hsieh and Ashwell (2010). The ratio works across heights because it compares the waist with the person's own height.
These ratios are screening figures and not medical advice. They do not diagnose any condition. Talk to a doctor if your ratio is above a limit, if you have a family history of heart disease or diabetes, or if your weight is changing without a clear cause.
Waist-hip ratio = waist (cm) / hips (cm)
Waist-to-height ratio = waist (cm) / height (cm)
WHO limit: men above 0.90, women above 0.85; waist-to-height above 0.5How to measure
- Use a flexible tape measure that does not pull the skin, and keep it level all the way round.
- Breathe out normally before you read the waist figure, and do not hold your stomach in.
- Measure the hips at the widest part of the buttocks, with your feet together.
What the ratios do not show
- Muscle and body fat: a muscular person with a high ratio may still be healthy, and a person of normal weight can carry too much fat around the middle.
- Pregnancy: waist and hip measurements change in pregnancy, so the figures are not meant for pregnant women.
- Age, ethnicity and the health risks a doctor would consider with a full assessment.
Worked example: woman, waist 80 cm, hips 100 cm, height 165 cm
The waist-hip ratio is 80 / 100 = 0.80. The WHO limit for women is 0.85, so the ratio is at or below the limit.
The waist-to-height ratio is 80 / 165 = 0.48, which is below the 0.5 boundary.
| Measure | Result | Against the limit |
|---|---|---|
| Waist-hip ratio | 0.80 | At or below 0.85 (women) |
| Waist-to-height ratio | 0.48 | 0.5 or below |
Frequently asked questions
Why are the WHO limits different for men and women?
The WHO sets a lower waist-hip limit for women, 0.85, than for men, 0.90, because the typical shapes of the two groups differ. The limits here follow the WHO figures for each sex.
Is the waist-to-height ratio better than waist size alone?
The Browning, Hsieh and Ashwell review proposed the 0.5 boundary as a simple check that works across heights. It is a screening figure, not a diagnosis.
What should I do if my ratio is above the limit?
See a doctor. They can measure blood pressure, blood sugar and cholesterol and advise on the next steps. A high ratio is a reason to check, not a diagnosis.
Can I use this for a child?
No. These limits are for adults. A child's waist should be read against growth charts by a doctor.
Are my measurements stored?
No. The ratios are calculated in your browser and nothing you enter is sent to us.
Sources
- WHO: Waist circumference and waist-hip ratio, report of a WHO expert consultation (2011)
- Waist-hip ratio: WHO cut-offs (Wikipedia)
- Waist-to-height ratio: 0.5 boundary, Browning et al. 2010 (Wikipedia)
Figures and text last checked on Tuesday, November 10, 2026.