Transparent method
The formula
Worked example
Example inputs
How to interpret the result
Waist-to-hip ratio captures something BMI can't see at all: where body fat is actually distributed, not just how much of it there is relative to height. Two people with the identical BMI can carry meaningfully different waist-to-hip ratios, and that distribution pattern is exactly why the two measures are meant to be read together, not as substitutes.
Before you rely on it
What to check
Use waist-to-hip ratio alongside BMI, not as a replacement for it. The two measure genuinely different things, and neither one alone tells the fuller story.
The common error
Where people go wrong with waist-to-hip ratio calculator
Treating waist-to-hip ratio as a more accurate alternative to BMI rather than a complementary measure. They capture different information, and dropping one in favor of the other loses part of the picture either way.
Sensitivity evidence
How waist circumference changes the waist-to-hip ratio
| Waist circumference | Waist-to-hip ratio | Waist-to-height ratio |
|---|---|---|
| 27 | 0.675 | 0.403 |
| 31 | 0.775 | 0.463 |
| 34worked example | 0.85 | 0.507 |
| 37 | 0.925 | 0.552 |
| 41 | 1 | 0.612 |
Every input, tested
Which input moves the waist-to-hip ratio most
| Input | Tested from | To | Waist-to-hip ratio at each end | Swing |
|---|---|---|---|---|
| Hip circumference | 36 | 44 | 0.944 to 0.773 | 0.172 (20%) |
| Waist circumference | 31 | 37 | 0.775 to 0.925 | 0.15 (18%) |
| Height | 60 | 74 | 0.85 to 0.85 | none |
Two variables at once
Waist-to-hip ratio by waist circumference and hip circumference
| Waist circumference \ Hip circumference | 32 | 40 | 48 |
|---|---|---|---|
| 27 | 0.844 | 0.675 | 0.563 |
| 31 | 0.969 | 0.775 | 0.646 |
| 34 | 1.1 | 0.85 | 0.708 |
| 37 | 1.2 | 0.925 | 0.771 |
| 41 | 1.3 | 1 | 0.854 |
Step by step
The worked example, input by input
| Input | Value used | What it means |
|---|---|---|
| Waist circumference | 34 | Measured at the navel, in inches. |
| Hip circumference | 40 | Measured at the widest point, in inches. |
| Height | 67 | Height in inches. |
| Waist-to-hip ratio | 0.85 | |
| Waist-to-height ratio | 0.507 | |
Inputs, definitions and assumptions
Waist circumference
Measured at the navel, in inches.
Hip circumference
Measured at the widest point, in inches.
Height
Height in inches.
Where the inputs come from
Measure your waist at the narrowest point between the ribs and hips, or at the level of the navel, and your hips at the widest part of the buttocks, standing with feet together and the tape parallel to the floor. Take the reading after breathing out normally, without pulling the tape tight. Height is used for the waist-to-height ratio. Use the same units for every measurement, and measure twice to check.
When the result stops applying
The ratio does not capture total body fat, muscle or fitness, and thresholds vary by ethnicity and age. Measurement error is common, so small changes are not meaningful. It is a screening measure, not a diagnosis. Pregnancy, bloating and some conditions change the numbers.
What to compare it with
Combine with the BMI and body fat percentage calculators for a fuller view, and see the healthy weight range page. The blood pressure and cholesterol calculators cover other risk markers. Ask a clinician to interpret results with your history.
People also ask
Frequently asked questions
What is a healthy waist-to-hip ratio?
The WHO cutoffs for abdominal obesity are above about 0.90 for men and 0.85 for women, with lower values associated with less cardiovascular risk.
Why is belly fat riskier than fat elsewhere?
Fat around the organs releases inflammatory and metabolic substances that raise the risk of heart disease and type 2 diabetes.
What is the waist-to-height rule?
Keeping your waist circumference under half your height is a simple guideline linked to lower cardiometabolic risk.