Waist-to-height ratio is one of the simplest numbers to track, and the ranges are easy to remember once you see them laid out. It needs only a tape measure and your height, and it works for most adults without separate charts for men and women.
Quick answer: Divide your waist by your height in the same units. UK guidance from NICE (NG246, 2025) describes a ratio of 0.4 to 0.49 as healthy central adiposity, 0.5 to 0.59 as increased risk, and 0.6 or above as high risk. The 0.5 threshold is usually summarized as keeping your waist under half your height. It is a screening number, not a diagnosis.
The chart
| Ratio | Common interpretation | Source of the bands |
|---|---|---|
| Below 0.40 | Not classified as a risk category by NICE; ask a clinician if it comes with unintended weight loss or undernutrition | Not defined in NG246 |
| 0.40 to 0.49 | Healthy central adiposity; no increased health risk indicated | NICE NG246 |
| 0.50 to 0.59 | Increased central adiposity; increased health risk | NICE NG246 |
| 0.60 or higher | High central adiposity; further increased health risk | NICE NG246 |
NICE says these bands can be used for adults with a BMI under 35 kg/m2, of both sexes and all ethnicities, including people with high muscle mass. You can read the wording in the NICE guideline chapter on identifying and assessing central adiposity.
What your waist should be: a lookup by height
If you know your height, you can skip the division. This table shows the waist measurement at which the ratio reaches 0.5 (half your height) and 0.6.
| Height | Waist at 0.5 | Waist at 0.6 |
|---|---|---|
| 60 in (152 cm) | 30.0 in (76 cm) | 36.0 in (91 cm) |
| 63 in (160 cm) | 31.5 in (80 cm) | 37.8 in (96 cm) |
| 66 in (168 cm) | 33.0 in (84 cm) | 39.6 in (101 cm) |
| 68 in (173 cm) | 34.0 in (86 cm) | 40.8 in (104 cm) |
| 70 in (178 cm) | 35.0 in (89 cm) | 42.0 in (107 cm) |
| 72 in (183 cm) | 36.0 in (91 cm) | 43.2 in (110 cm) |
| 74 in (188 cm) | 37.0 in (94 cm) | 44.4 in (113 cm) |
Use the waist-to-height ratio calculator for exact values, and measure carefully using our guide to measuring waist circumference. A one-inch error in the tape changes the ratio by 0.015 or more, which is enough to move you between bands.
Worked examples
Inches. At 5 feet 8 inches (68 inches), half of height is 34 inches. A waist of 36 inches gives 36 / 68 = 0.53, in the increased-risk band. If the waist came down to 34 inches, the ratio would be 34 / 68 = 0.50, right at the line.
Centimeters. A person 172 cm tall with a 92 cm waist has 92 / 172 = 0.53. Someone 165 cm tall with a 90 cm waist has 90 / 165 = 0.55. Always use the same unit for both numbers; the units cancel and the ratio is the same whether you use inches or centimeters.
Comparing with the metabolic syndrome waist criterion. The U.S. criteria for metabolic syndrome count a waist of 40 inches (102 cm) or more in men and 35 inches (88 cm) or more in women as elevated. A man who is 70 inches tall with a 38-inch waist is below that cutoff but has a ratio of 38 / 70 = 0.54, already in the increased-risk band. A woman who is 64 inches tall with a 35-inch waist meets the metabolic syndrome criterion and has a ratio of 35 / 64 = 0.55. The ratio and the fixed cutoffs usually agree, but the ratio adjusts for body size, so it can flag shorter people sooner and taller people later.
What the research behind the 0.5 line shows
A 2012 systematic review and meta-analysis by Ashwell, Gunn, and Gibson in Obesity Reviews concluded that waist-to-height ratio is a better screening tool than waist circumference or BMI for adult cardiometabolic risk factors. The authors highlighted 0.5 as a boundary value that worked across sexes and many populations. The paper is available through its DOI link.
That work fed into official guidance: NICE’s 2022 guideline first recognized the ratio, and the 2025 update (NG246) sets out the bands above and tells clinicians to measure the ratio alongside BMI in adults with a BMI under 35. Screening tools like this are meant to prompt a closer look, not to replace blood pressure, glucose, and lipid testing.
Does it change with age?
NICE applies the same bands to adults of all ages. Some researchers have argued that slightly higher cutoffs may fit older adults because loss of muscle can lower body weight while fat stays centered on the abdomen, but there is no widely adopted separate chart. The ratio is not interchangeable for children and teenagers, who should be assessed by a pediatric clinician using growth charts. See waist-to-height ratio vs BMI for how the ratio compares with other measures.
Why the middle matters more than the scale
Fat stored around the abdomen, including visceral fat packed around organs, behaves differently from fat stored under the skin of the hips and thighs. It is more closely associated with insulin resistance, fatty liver, high triglycerides, and high blood pressure in population studies. That is the logic behind using a waist-based number: it is a rough, cheap stand-in for where weight is carried. It cannot see inside the body, so two people with the same ratio can have different amounts of visceral fat.
Tracking the ratio over time: an example
Single readings are noisy, so most people learn more from a trend. Here is an illustrative six-month record for a person 68 inches tall, measured once a month under the same conditions.
| Month | Waist (in) | Ratio (waist / 68) | Band |
|---|---|---|---|
| 0 | 38.0 | 0.56 | Increased risk |
| 2 | 37.5 | 0.55 | Increased risk |
| 4 | 36.5 | 0.54 | Increased risk |
| 6 | 35.5 | 0.52 | Increased risk |
The waist fell 2.5 inches and the ratio fell by about 0.04, yet the person is still in the 0.50 to 0.59 band. That is a normal pattern: bands are broad, and progress shows up in the direction of the numbers well before it crosses a line. A tape-measure error of one inch is about 0.015 on this ratio, so a drop from 0.56 to 0.55 in two months is within noise, while a drop of 0.04 across six months is more convincing. Pair it with blood pressure and lab trends, not instead of them.
Waist-to-height ratio versus fixed waist cutoffs
Metabolic syndrome criteria use a fixed waist in inches or centimeters; the ratio scales with height. Neither is better in every situation.
| Approach | Men | Women | Adjusts for height? |
|---|---|---|---|
| U.S. metabolic syndrome criterion | 40 in (102 cm) or more | 35 in (88 cm) or more | No |
| Lower cutoffs used for South and East Asian ancestry in some criteria | Lower than the U.S. values | Lower than the U.S. values | No |
| NICE waist-to-height ratio | 0.5 or higher is increased risk | 0.5 or higher is increased risk | Yes |
Common mistakes with the chart
- Mixing units. A waist in inches divided by a height in centimeters gives a meaningless number near 0.2.
- Measuring over clothing or at a different landmark each time. Pick one method and keep it.
- Using last year’s height. Height shrinks slightly with age; remeasure it occasionally.
- Reading one measurement as a trend. Day-to-day swings from meals and bloating can be an inch.
- Treating a good ratio as a clean bill of health. Labs and blood pressure still matter.
- Applying the adult chart to a child.
What to do with your ratio
A ratio above 0.5 is a prompt to look at blood pressure, glucose, triglycerides, and liver health, because central fat tends to travel with them. Our metabolic syndrome calculator counts five markers together, and the complete guide to visceral fat explains why abdominal fat matters. For food guidance see the metabolic syndrome diet article, and for the broader waist picture read waist circumference and belly fat. Discuss goals and pace with your clinician; the MedlinePlus metabolic syndrome page is a good overview. Do not change any medicine because of a ratio.
Questions to bring to your appointment
- Which waist-to-height range applies to me, given my age and health history?
- How often should I re-measure, and should we use the same tape and landmark each time?
- What other tests should accompany a ratio above 0.5?
- Does my ratio change how you read my blood pressure, glucose, and triglycerides?
- Is a BMI of 35 or higher a reason to use a different approach?
Frequently asked questions
What is a good waist-to-height ratio?
NICE’s 2025 guideline on overweight and obesity (NG246) describes 0.4 to 0.49 as healthy central adiposity, 0.5 to 0.59 as increased central adiposity with increased health risks, and 0.6 or more as high central adiposity with further increased risks. The simple message that goes with it is to keep your waist to less than half your height.
Is the chart the same for men and women?
Yes. NICE says the bands can be used for people with a BMI under 35 kg/m2 of both sexes and all ethnicities, including adults with high muscle mass. That is one reason the ratio is popular: it avoids separate male and female cutoffs. Metabolic syndrome criteria, by contrast, use different waist cutoffs for men and women.
Can I have a normal BMI and a high ratio?
Yes. NICE specifically notes that a person in the healthy-weight BMI range may still have central adiposity. A BMI of 24 with a waist-to-height ratio of 0.55 is possible when weight is carried around the middle.
Does the ratio apply to children?
NICE uses the same 0.5 message for children and young people aged 5 and over, but children should be assessed by a pediatric clinician, who will also use growth charts. Do not use an adult chart to label a child.
What if my ratio is below 0.4?
NICE’s healthy band starts at 0.4 and the guideline does not define a risk category below it. A very low ratio is usually unremarkable in a naturally lean person, but if it comes with unintended weight loss, weakness, or low appetite, mention it to a clinician.
How fast can the ratio change?
The arithmetic is simple. For a person 68 inches tall, every inch off the waist lowers the ratio by about 0.015. A 36-inch waist is 0.53, and 34 inches is exactly 0.50. Because tape-measure noise can be an inch, look at trends across months, not one day.
Does a ratio under 0.5 mean my labs are fine?
No. The ratio is a screening number. Blood pressure, fasting glucose or A1C, triglycerides, HDL, and liver tests are measured directly and can be abnormal at any waist size.
About the author: Charles Kirkland is the founder of Metabolic Clarity Labs and author of The Journey Back. He is not a physician. This is general education, not a medically reviewed treatment plan.
Sources checked October 31, 2026. Discuss personal decisions with a qualified clinician. Do not start, stop, or change prescribed treatment based on this article.
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