Quick answer
Waist-to-hip ratio = waist ÷ hip. A waist of 90 and hips of 100 give 0.9, at the WHO threshold for men.
Choose sex and enter waist and hip in the same unit. The calculator returns the ratio and a risk note.
Related tools: Waist-to-Height Ratio Calculator: Waist-to-height ratio. Healthy Weight Calculator: Weight range for a normal BMI at your height. BMI Calculator: Find your Body Mass Index (BMI) and weight status.
How to use the Waist-to-Hip Ratio Calculator
- Choose sex: Male and Female.
- Enter waist (cm) (above 0).
- Enter hip (cm) (above 0).
- Press Calculate to see the result, and use Reset to start again.
| Input | What to enter | Allowed values |
|---|---|---|
| Sex | Choose one: Male; Female | Starts at Male |
| Waist | A number, in cm | > 0 |
| Hip | A number, in cm | > 0 |
Formula and method
Formula
WHR = waist ÷ hip
IEEE-754 double precision; shown to 1 decimal place unless stated.
WHO cut-offs for substantially increased risk: above 0.90 (men) and above 0.85 (women). Informational estimate, not medical advice. Talk to a qualified health professional about your own situation.
Worked examples
This example is verified: each one is an automated test case that the live calculator must reproduce exactly.
Example 1
Inputs: Sex = Male; Waist = 90; Hip = 100.
| Result | Value |
|---|---|
| Waist-to-hip ratio | 0.9 |
| Risk | Below WHO threshold |
The first line is the headline result (waist-to-hip ratio). Below it the waist-to-Hip Ratio Calculator lists risk, which describe the same case from other angles. IEEE-754 double precision; shown to 1 decimal place unless stated.
WHO thresholds
The WHO defines abdominal obesity as a ratio above 0.90 for men and 0.85 for women. A ratio of 0.9 is therefore right at the limit for a man.
Measure properly
Measure the waist at the narrowest point or the midpoint between rib and hip bone, and hips at the widest point. Same unit for both. It's a risk indicator, not a diagnosis.
How the result changes with waist
Holding every other input at the first worked example, this table changes only waist. It shows how sensitive the answer is to that one value; each row was produced by running this calculator.
| Waist | Waist-to-hip ratio | Risk |
|---|---|---|
| 45 | 0.45 | Below WHO threshold |
| 90 | 0.9 | Below WHO threshold |
| 180 | 1.8 | Above WHO threshold |
| 360 | 3.6 | Above WHO threshold |
What happens with invalid input
These messages are produced by the calculator itself, so you know what to fix.
- Hip: entering "0" shows "Hip must be greater than 0." beside that field and no result.
Choosing between the Waist-to-Hip Ratio Calculator and similar calculators
Each row shows what a related calculator on this site asks for and what it returns, so you can pick the one that matches your question.
| Calculator | You enter | It returns |
|---|---|---|
| [Waist-to-Height Ratio Calculator](/health/waist-height-ratio/) | waist and height | Waist-to-height ratio |
| [Healthy Weight Calculator](/health/healthy-weight/) | height | Healthy weight range |
| [BMI Calculator](/health/bmi-calculator/) | units, weight and height | Your BMI |
| [Height Calculator](/health/height-calculator/) | convert | Height |
| [Body Fat Calculator (U.S. Navy)](/health/body-fat/) | sex, height and neck | Estimated body fat |
Background: body measurements and screening
Body-measurement ratios are screening tools, not diagnoses. BMI ignores body composition and fat distribution, and reviews find waist-to-hip and waist-to-height ratios are useful additions but not clearly better than BMI or waist circumference alone. Where the tape goes matters, so measure at the same sites each time.
Some sources quote a waist-to-hip ratio above 0.8 for women and 0.95 for men as a marker of increased metabolic risk; treat that as a screening flag, and talk to a clinician about what your own numbers mean.
Assumptions and limitations
- Measurements in the same unit
- Not a diagnosis
This calculator gives general information based on published formulas. It is not medical advice, and it cannot account for your health history. Talk to a qualified clinician about decisions that affect your health.
If a required value is empty, not a number, or outside its allowed range, the form marks that field with a message and shows no result instead of a misleading number. The automated checks deliberately try invalid entries for hip to confirm this.
Frequently asked questions
What is a healthy waist-to-hip ratio?
Below 0.90 for men and 0.85 for women.
Why does it matter?
Abdominal fat links to heart disease.
Does body shape matter?
Yes, pear shapes are lower risk.
What does the Waist-to-Hip Ratio Calculator calculate?
Waist-to-hip ratio and WHO risk threshold. It returns Waist-to-hip ratio and Risk.
What formula does the Waist-to-Hip Ratio Calculator use?
WHR = waist ÷ hip. WHO cut-offs for substantially increased risk: above 0.90 (men) and above 0.85 (women).
What do I need to enter in the waist-to-Hip Ratio Calculator?
You enter Sex, Waist (cm) and Hip (cm).
How is the result rounded or limited?
IEEE-754 double precision; shown to 1 decimal place unless stated. Measurements in the same unit.
What are the limits of this calculator?
Measurements in the same unit. Not a diagnosis.
What does the “Sex” option change?
It sets how the waist-to-Hip Ratio is worked out. The choices are Male and Female.
What is an example of a waist-to-Hip Ratio result?
With sex Male, waist 90 and hip 100, the waist-to-hip ratio is 0.9.
Where does the method come from?
The method follows: WHO, Waist Circumference and Waist–Hip Ratio: Report of a WHO Expert Consultation (2008).
Can I rely on this calculator for a decision?
This calculator gives general information based on published formulas. It is not medical advice, and it cannot account for your health history. Talk to a qualified clinician about decisions that affect your health. For this calculator in particular: Measurements in the same unit.
Related calculators
- Waist-to-Height Ratio Calculator — Waist-to-height ratio.
- Healthy Weight Calculator — Weight range for a normal BMI at your height.
- BMI Calculator — Find your Body Mass Index (BMI) and weight status.
- Height Calculator — Convert height between centimeters and feet-and-inches.
- Body Fat Calculator (U.S. Navy) — Estimate body fat percentage from tape measurements (U.S. Navy method).
- Ideal Weight Calculator — Ideal body weight by four published formulas (Devine, Robinson, Miller, Hamwi).
Sources
- WHO, Waist Circumference and Waist–Hip Ratio: Report of a WHO Expert Consultation (2008)
Content last reviewed 2026-11-04. Formulas and worked examples are checked by automated tests against independently computed values.