Where you carry weight matters as well as how much you weigh. Fat around the middle is linked with higher health risk than fat on the hips and thighs. This free calculator checks your waist-to-height ratio and, if you add your hip size, your waist-to-hip ratio, and compares your waist with commonly used cutoffs.
How to measure your waist and hips
- Stand up straight, relaxed, and use a flexible tape measure. Keep it level with the floor and snug but not squeezing.
- Waist: measure around the middle, level with your navel, after breathing out normally. Do not hold your breath or pull your stomach in.
- Hips: measure around the widest part of the hips and buttocks.
- Use the same units for every box, and measure over bare skin or thin clothing.
Waist-to-height ratio
Divide your waist measurement by your height, in the same units. A simple rule: keep your waist to less than half of your height. For someone 170 cm (5 ft 7 in) tall, that means a waist under 85 cm (33.5 in). Because it uses your own height, the ratio works for tall and short adults alike, and it does not need separate rules for men and women.
| Ratio | What it suggests |
|---|---|
| Below 0.4 | Lower than the usual range. Often fine in slim people, but can go with being underweight. |
| 0.4 to 0.49 | Healthy range |
| 0.5 to 0.59 | Increased health risk |
| 0.6 and above | High health risk |
Waist-to-hip ratio and waist size
The waist-to-hip ratio is your waist divided by your hips. The World Health Organization describes abdominal obesity as a ratio above 0.90 for men and above 0.85 for women. Waist size on its own is also used: a waist above 102 cm (40 in) for men or 88 cm (35 in) for women is linked with substantially higher risk. Some guidelines flag a smaller increase in risk from 94 cm (37 in) for men and 80 cm (31.5 in) for women.
| Measure | Men | Women |
|---|---|---|
| Waist-to-hip ratio (WHO) | Above 0.90 | Above 0.85 |
| Waist size, higher risk | Above 102 cm (40 in) | Above 88 cm (35 in) |
| Waist-to-height ratio | Keep below 0.5 | Keep below 0.5 |
What these numbers can and cannot tell you
These ratios are screening tools, not diagnoses. They can be less reliable for children, during pregnancy, for very muscular people and for some body types. They work best alongside other information such as your BMI, blood pressure, blood sugar and cholesterol. A healthy ratio does not guarantee good health, and a higher one does not mean disease.
Habits that help the waistline
- Move every day. Even walking helps: see how much walking you need.
- Prioritize sleep, which affects appetite and weight: 8 sleep habits.
- Eat more fiber-rich foods, as in our fiber guide.
- Estimate a body fat percentage with the body fat calculator.
See a professional if…
- Your ratio is in the higher-risk range. A check-up can look at blood pressure, blood sugar and cholesterol.
- Your waist has grown quickly or you have unexplained swelling or pain in your abdomen.
Frequently asked questions
What is a good waist-to-height ratio?
A ratio from 0.4 to 0.49 is generally considered healthy. The simple rule is to keep your waist measurement below half of your height.
Is waist-to-height ratio better than BMI?
It adds useful information because it reflects belly fat, which BMI cannot see. Many experts suggest using both, together with other health checks.
What is a healthy waist-to-hip ratio?
The WHO uses 0.90 for men and 0.85 for women as the point above which abdominal obesity is defined. Lower is generally better, but it varies with body type.
Can children use this calculator?
The simple 0.5 rule has been studied in children too, but the categories here are for adults. Ask your child’s pediatrician to interpret measurements.
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This calculator provides general estimates for healthy adults and is for information only. It is not medical advice and does not replace a conversation with a qualified healthcare professional. Read our disclaimer and editorial policy.