How to Measure Your Waist and Hips

Use a tape that does not stretch. Stand relaxed with your arms at your sides and your weight even on both feet.

• Waist. Stand with your feet about 25 to 30 cm apart. Place the tape halfway between your lowest rib and the top of your hip bone, roughly in line with your belly button. Put it on your skin or over one light layer, then breathe out normally and read it.
• Hips. Stand with your feet together. Place the tape around the widest part of your buttocks, parallel to the floor.
• Tightness. Keep the tape snug, without squeezing your skin.
• Repeat. Take each measurement twice. If the two readings differ by more than 1 cm, take a third and use the average of the two closest. Otherwise, use the average of the two (AIHW).

Schematic only, not to scale.

How the Calculation Works

The ratio is your waist divided by your hips, both in the same unit, so the answer has no unit. A waist of 80 cm and hips of 100 cm give 80 / 100 = 0.80. The calculator shows two decimal places and compares that figure with the cut-off. At these sizes, 1 cm more on the waist moves the ratio by 0.01, so careful measuring matters near a cut-off.

The same ratio can come with very different waist sizes, which is why the calculator shows both checks. Here are two worked examples for women:

The Cut-offs Behind the Result

The WHO report table links the ratio figures with a substantially increased risk of metabolic complications. The figures trace to a 1999 WHO working definition of abdominal obesity, one part of its definition of metabolic syndrome: blood sugar or insulin problems together with other factors, such as raised blood pressure. That definition says "above" these figures. The 2008 report lists them as "or more", in a table of figures it calls often attributed to WHO, and this calculator follows the table. A result right on the line is not a sharp divide, because a 1 cm difference in measuring can move the ratio by about 0.01. The waist sizes are the healthdirect figures for risk of disease.

The expert group behind the 2008 report said that making definitive decisions on cut-offs was outside its scope. healthdirect, Better Health Channel and the Australian Obesity Management Algorithm give cut-offs for waist size, and none of the three gives one for the ratio.

A 2005 Australian Government data standard (AIHW) lists a wider range for the ratio: 0.8 to 0.9 for women and 0.9 to 1.0 for men. It notes that the 1995 National Nutrition Survey used above 0.8 for women and above 0.9 for men, so a woman at 0.82 sits below the WHO line and above that survey line. The standard adds that these values may not suit all age and ethnic groups. It also says the ratio is no longer a commonly used measure, because waist size, alone or with other metabolic measures, is a better indicator of risk.

Some online charts split the ratio into low, moderate and high bands. Those bands are not in the WHO report, so this calculator does not use them.

Why Your Waist Can Tell You More Than Your Weight

The scales cannot show where fat sits. The distribution of fat is more important than the amount when assessing disease risk, and waist size is thought to be a better predictor of health risk than BMI (Better Health Channel). Some people with a BMI in the normal or overweight range still have abdominal obesity, particularly older adults who have lost muscle (Australian Obesity Management Algorithm).

Waist size is also a guide to visceral fat, the type that coats your organs. Too much of it can increase the risk of cardiovascular disease, metabolic syndrome, type 2 diabetes and some cancers (healthdirect). To learn more, read what visceral fat is and why it matters. For the height and weight check, use the BMI calculator and healthy BMI range.

The evidence does not settle which measure is best. The WHO report says it is unclear which of BMI, waist size, the ratio or hip size best predicts cardiovascular disease in adults. It also notes that measuring hips may be harder than measuring the waist alone, which could limit the ratio's use.

Where These Checks Fall Short

• Who they suit. Waist measurements do not apply to children, pregnant people, people whose abdomen is very enlarged by a health issue, or people from certain non-European backgrounds.
• Background. The Australian Obesity Management Algorithm lists lower waist figures for Asian populations, and recommends them for Aboriginal and Torres Strait Islander peoples: over 80 cm for women and over 90 cm for men. Some studies also suggest a lower ratio cut-off for Asian women, for example 0.80.
• Larger bodies. A waist measurement can be less reliable for people living with overweight or obesity.
• Measuring method. Waist figures differ between measuring sites, so keep to the same method each time.

What to Do With Your Result

One ratio does not describe your health. If either check concerns you, a GP or nurse practitioner can look at it with your wider health. Australia's guidelines on healthy eating and physical activity are a starting point:

• Healthy eating. Build meals from the five food groups, and limit foods and drinks with saturated fat, added salt, added sugars and alcohol.
• Physical activity. Australia's guidelines for adults suggest 30 minutes or more of moderate to vigorous physical activity on most days, plus muscle-strengthening activities on 2 or more days a week.

If you and your GP or nurse practitioner decide that weight is worth looking at, these guides cover the basics. Read what a calorie deficit is and how to work out yours, use the calorie deficit calculator, or see how many steps a day to lose weight and what exercise can and cannot do for belly fat. For fat around the middle, read what the evidence says about belly fat and what causes a beer belly. For a step by step plan, see how to lose weight: a realistic guide. Outcomes vary between individuals.

Frequently Asked Questions

How do I calculate my waist to hip ratio?

You divide your waist measurement by your hip measurement, using the same unit for both. A waist of 75 cm and hips of 100 cm give a ratio of 0.75. Inches give the same answer, because the unit cancels out. The calculator above takes centimetres, because the waist check uses them.

What is an ideal waist to hip ratio?

The WHO report gives a risk line, not an ideal figure, and the Australian sources on this page set no ideal ratio either. The WHO table gives one line for each sex: 0.85 or more for women and 0.90 or more for men is linked with a higher risk of metabolic complications. A ratio under that line is not a target, and it does not rule out a health risk.

What is the difference between the waist and the hips?

The two sites sit at different levels. Your waist is measured halfway between your lowest rib and the top of your hip bone, roughly in line with your belly button. Your hips are measured lower down, around the widest part of your buttocks, so the hip bone itself is only a landmark for the waist.

What waist size is considered abdominal obesity?

The Australian Obesity Management Algorithm classes a waist over 88 cm for women and over 102 cm for men as abdominal obesity in the general population. Its figures for Asian populations are lower, and it recommends those for Aboriginal and Torres Strait Islander peoples. A GP or nurse practitioner reads your waist size with your BMI and related conditions. See what overweight and obesity mean.

Does the waist to hip ratio cut-off change with age?

The WHO table does not change with age: it gives figures by sex only, so this calculator does not ask for yours. That does not mean age makes no difference. The same report describes substantial evidence that the ratio varies with sex and age, and an Australian data standard says the values may not suit all age groups.

Can my waist to hip ratio change if my weight changes?

Yes, it can. In one long-term US study, waist and hip sizes moved with weight. The waist changed more than the hips in men, and the two changed similarly in women. To look at your weight, start with healthy eating and physical activity, and what the evidence says about belly fat covers the detail. Outcomes vary between individuals.

References

• World Health Organization. Waist circumference and waist-hip ratio: report of a WHO expert consultation, Geneva, 8-11 December 2008. https://iris.who.int/server/api/core/bitstreams/ca408ade-05c9-4b7c-8967-6ee5b5e0ccd8/content
• healthdirect. Body mass index (BMI) and waist circumference. https://www.healthdirect.gov.au/procedures/health-screenings/body-mass-index-bmi-and-waist-circumference
• Better Health Channel (Victorian Government). Body mass index (BMI). https://www.betterhealth.vic.gov.au/health/healthyliving/body-mass-index-bmi
• Markovic TP, et al. The Australian Obesity Management Algorithm (July 2024). https://www.diabetessociety.com.au/wp-content/uploads/2024/07/Australian-Obesity-Management-Algorithm-July-2024.pdf
• Eat for Health (NHMRC). Australian dietary guidelines 1 to 5. https://www.eatforhealth.gov.au/guidelines/australian-dietary-guidelines-1-5
• Australian Government Department of Health, Disability and Ageing. Recommendations for adults (18 to 64 years). https://www.health.gov.au/topics/physical-activity/24-hour-movement-guidelines-for-all-australians/recommendations-for-adults-18-to-64-years
• Australian Institute of Health and Welfare (METEOR). Adult, waist-to-hip ratio, N.NN. https://meteor.aihw.gov.au/content/270207
• Australian Institute of Health and Welfare (METEOR). Person, hip circumference (measured). https://meteor.aihw.gov.au/content/270366
• Australian Institute of Health and Welfare (METEOR). Person, waist circumference (measured). https://meteor.aihw.gov.au/content/270129

This page is general information only and does not replace individual medical advice. Please speak with a registered Australian healthcare practitioner about your own circumstances.