Waist-to-hip ratio is one of the simplest ways to describe where body fat sits. The formula takes seconds, but the interpretation depends on sex, age, ethnicity and how the measurement was taken. This guide gives you the charts, the official thresholds and the caveats in one place.
Waist-to-hip ratio is waist circumference divided by hip circumference, both measured at their designated landmarks. Because it is a ratio, the unit cancels: 72 cm divided by 94 cm gives the same 0.766 as 28.3 inches divided by 37.0 inches.
WHR = waist ÷ hip
Example: 74 cm waist and 96 cm hip → 74 ÷ 96 = 0.771.
Use the same unit for both measurements and keep the tape level. Round the final ratio to two decimal places; the thresholds sit at 0.85 and 0.90, so rounding to one decimal can move a result across the line. The calculator reports two decimals for this reason.
The World Health Organization uses waist-to-hip ratio as a marker of abdominal fat distribution. Its widely cited cutoffs are simple:
| Sex | Lower risk | Elevated risk |
|---|---|---|
| Women | Below 0.85 | 0.85 or above |
| Men | Below 0.90 | 0.90 or above |
These are screening thresholds, not diagnostic categories. A ratio below the cutoff does not guarantee low risk, and a ratio above it does not mean disease is present. They indicate that fat is stored disproportionately around the waist and that further assessment may be worthwhile.
Some charts add a third band — for example, “low”, “moderate” and “high” — or use different cutoffs for different populations. Those variations are not necessarily wrong, but they are not the WHO's thresholds. When a chart does not cite its source, treat the numbers as approximate.
The table below is a descriptive aid, not a health classification. It shows how common shape labels usually map to waist-to-hip ratios in women. Men tend to sit higher for the same visual silhouette because the hip is narrower.
| Typical silhouette | Waist-to-hip ratio (women) | What drives the number |
|---|---|---|
| Pronounced hourglass | Around 0.65–0.75 | Waist much narrower than hip |
| Moderate hourglass | Around 0.75–0.80 | Defined waist, balanced chest and hip |
| Pear | Often 0.70–0.82 | Hip wider than chest; waist may still be narrow |
| Rectangle | Around 0.80–0.88 | Little waist indentation |
| Apple | Often 0.85 and above | Waist is the widest of the three |
The overlaps are real. A pear shape can have a ratio of 0.70 or 0.82 depending on how narrow the waist is. That is why the shape classification checks chest-to-hip width as well as the waist ratio.
Example 1 — 68 cm waist, 92 cm hip. 68 ÷ 92 = 0.739. For a woman, this is below 0.85. For a man with the same numbers, it is also below 0.90, but the silhouette may read differently because the chest and shoulder width are not in the formula.
Example 2 — 84 cm waist, 96 cm hip. 84 ÷ 96 = 0.875. For a woman, this is above 0.85; for a man, it is below 0.90. The same body can be flagged for one sex and not the other because the thresholds differ.
Example 3 — 33 inches waist, 40 inches hip. 33 ÷ 40 = 0.825. In centimetres, 83.8 ÷ 101.6 gives the same 0.825. The unit conversion does not change the ratio, which is why you can use whichever tape you have.
Quick check: if the waist is 80% of the hip, the ratio is 0.80. If it is 90% of the hip, the ratio is 0.90. Most people can estimate the ratio within a few hundredths by comparing the two tape readings before dividing.
BMI compares weight to height. It cannot tell whether the weight is muscle, subcutaneous fat or visceral fat around the organs. Waist-to-hip ratio adds distribution information: it rises when fat accumulates around the waist relative to the hip.
That is why two people with the same BMI can have different ratios and different risk profiles. A muscular person with a narrow waist may have a high BMI and a low ratio; a person with a normal BMI but a large waist may have a high ratio. Neither number is complete on its own.
The Navy body fat estimate adds a third view by estimating total fat percentage from circumference. Used together, BMI, waist-to-hip ratio and body fat give a more rounded picture than any one alone.
Bone structure. Hip width includes bone, not just fat. A person with wide hip bones can have a low ratio without much fat around the hip, and a person with narrow hips can have a higher ratio at the same waist.
Age. Fat tends to redistribute toward the waist with age, and muscle mass tends to fall. A ratio that was 0.78 at 25 may be 0.84 at 55 without a large change in weight. The thresholds are not age-specific, but the trend with age is real.
Ethnicity. Body-fat distribution and risk at a given waist circumference vary across populations. Some guidelines use lower waist cutoffs for Asian populations. A single global ratio chart is a rough tool.
Pregnancy and medical conditions. Pregnancy, ascites, large fibroids and some medications change abdominal circumference. The ratio is not meaningful in those contexts without clinical interpretation.
Measurement error. A tape placed at the navel instead of the narrowest waist, or over thick clothing, can shift the ratio by several hundredths. Consistency matters more than a single perfect reading.
The ratio and the waist circumference answer related but different questions. Waist circumference measures absolute abdominal size; the ratio compares that size with hip size. A person with a large waist and large hips can have a normal ratio but an elevated waist circumference. A person with a small waist and narrow hips can have a normal waist circumference but a higher ratio.
That is why the two are usually read together. For health screening, waist circumference has clearer action levels, while the ratio adds information about how the weight is distributed. For clothing, the ratio is more relevant to silhouette because it describes the waist-to-hip transition.
Neither number measures body fat directly. A muscular person can have a larger waist circumference without excess fat, and a lean person can have a higher ratio because of bone structure. Use the chart as a screening aid and interpret it with those caveats in mind.
Measure the waist at the narrowest point or at the midpoint between the lowest rib and the top of the hip bone. Measure the hip at the widest point of the seat, feet together. Keep the tape level, breathe out normally, and do not pull it tight enough to compress the skin.
Take each measurement twice and average. If the two waist readings differ by more than 2 cm, reposition the tape and try again. The full technique is in how to measure your waist and hips.
Record the date, the numbers and the method. A ratio without that context is hard to compare over time.
The standard WHO cutoffs do not change with age: 0.85 for women and 0.90 for men. But the ratio itself tends to rise with age. Fat redistributes toward the abdomen, muscle mass often falls, and hip circumference may change less than waist circumference. A woman who measured 0.78 at 25 may measure 0.84 at 55 without a large change in weight.
This does not mean the threshold is wrong for older adults. It means a given ratio should be read alongside age, waist circumference and other risk factors. Some clinicians use age-specific percentiles to compare a person with their peers, but that is a different question from “is this above the WHO screening cutoff”.
If you are tracking your own ratio over years, expect a gradual upward drift and interpret it in context. A sudden jump over a few months is more likely to reflect measurement changes, fluid, pregnancy or a medical issue than a genuine change in fat distribution.
Why do some charts use 0.80 for women? Some studies and fitness sources use 0.80 as an “optimal” or “low-risk” reference, often derived from different populations or from attractiveness research. The WHO screening threshold for elevated risk is 0.85. The two numbers answer different questions, so do not mix them.
Why is the male threshold higher? Men tend to store more fat around the waist and have narrower hips, so the same ratio corresponds to a different amount of abdominal fat. The 0.90 cutoff is calibrated for that pattern.
Can I use the chart for a child or teenager? No. Children and adolescents have different body proportions and growth patterns. Paediatric assessment uses age- and sex-specific references and should be interpreted by a clinician.
What if I am pregnant? Pregnancy changes waist circumference substantially. The ratio is not a meaningful screening tool during pregnancy. Use the guidance from your maternity care provider.
The WHO marks below 0.85 for women and below 0.90 for men as lower risk. These are screening thresholds, not guarantees. Waist circumference, blood pressure, glucose and other factors also matter.
A ratio of 0.70 is below the WHO thresholds for both women and men, so it is not flagged as elevated by this measure. It does not by itself confirm health, and a ratio that is very low can reflect narrow hips or low muscle mass rather than low risk.
Yes. The formula is the same, but the risk threshold is higher at 0.90 because men typically store more fat around the waist and have narrower hips. The shape labels are used less often for men, but the ratio is still informative.
This is an editorial reference, not medical advice. Body shape and body fat estimates describe proportions; they do not diagnose health.
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