Quick answer
Waist-to-height ratio = waist ÷ height. A waist of 80 cm and height of 175 cm gives 0.457, below the 0.5 threshold.
Enter waist and height in the same unit. The calculator returns the ratio and a risk note.
Related tools: Waist-to-Hip Ratio Calculator: Waist-to-hip ratio and WHO risk threshold. Height Calculator: Convert height between centimeters and feet-and-inches. BMI Calculator: Find your Body Mass Index (BMI) and weight status.
How to use the Waist-to-Height Ratio Calculator
- Enter waist (cm) (above 0).
- Enter height (cm) (above 0).
- Press Calculate to see the result, and use Reset to start again.
| Input | What to enter | Allowed values |
|---|---|---|
| Waist | A number, in cm | > 0 |
| Height | A number, in cm | > 0 |
Formula and method
Formula
WHtR = waist ÷ height
IEEE-754 double precision; shown to 1 decimal place unless stated.
A ratio of 0.5 or above is commonly used as a threshold for increased health risk. Informational estimate, not medical advice. Talk to a qualified health professional about your own situation.
Worked examples
These examples are verified: each one is an automated test case that the live calculator must reproduce exactly.
Example 1
Inputs: Waist = 80; Height = 175.
| Result | Value |
|---|---|
| Waist-to-height ratio | 0.457 |
| Risk | Below 0.5 |
Example 2
Inputs: Waist = 95; Height = 175.
| Result | Value |
|---|---|
| Waist-to-height ratio | 0.543 |
| Risk | At or above 0.5 |
The first line is the headline result (waist-to-height ratio). Below it the waist-to-Height Ratio Calculator lists risk, which describe the same case from other angles. IEEE-754 double precision; shown to 1 decimal place unless stated.
The 0.5 rule
The simple guidance 'keep your waist less than half your height' is based on studies linking a ratio above 0.5 to higher cardiometabolic risk. UK NICE guidance lists 0.5 to 0.59 as increased risk and 0.6 or more as high risk.
Measuring the waist
Measure at the midpoint between the lowest rib and the top of the hip bone, after breathing out. Use the same units for both. The ratio is a screening tool, 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-height ratio | Risk |
|---|---|---|
| 40 | 0.229 | Below 0.5 |
| 80 | 0.457 | Below 0.5 |
| 160 | 0.914 | At or above 0.5 |
| 320 | 1.829 | At or above 0.5 |
What happens with invalid input
These messages are produced by the calculator itself, so you know what to fix.
- Height: entering "0" shows "Height must be greater than 0." beside that field and no result.
Choosing between the Waist-to-Height 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-Hip Ratio Calculator](/health/waist-hip-ratio/) | sex, waist and hip | Waist-to-hip ratio |
| [Height Calculator](/health/height-calculator/) | convert | Height |
| [BMI Calculator](/health/bmi-calculator/) | units, weight and height | Your BMI |
| [Body Fat Calculator (U.S. Navy)](/health/body-fat/) | sex, height and neck | Estimated body fat |
| [Ideal Weight Calculator](/health/ideal-weight-calculator/) | units, sex and height | Ideal weight (Devine) |
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
- Same units
- 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 height to confirm this.
Frequently asked questions
Is it better than BMI?
It captures abdominal fat.
What ratio is healthy?
Below 0.5 for most adults.
Does it work for children?
A 0.5 cut-off is also used for children.
What does the Waist-to-Height Ratio Calculator calculate?
Waist-to-height ratio. It returns Waist-to-height ratio and Risk.
What formula does the Waist-to-Height Ratio Calculator use?
WHtR = waist ÷ height. A ratio of 0.5 or above is commonly used as a threshold for increased health risk.
What do I need to enter in the waist-to-Height Ratio Calculator?
You enter Waist (cm) and Height (cm).
How is the result rounded or limited?
IEEE-754 double precision; shown to 1 decimal place unless stated. Same units.
What are the limits of this calculator?
Same units. Not a diagnosis.
What is an example of a waist-to-Height Ratio result?
With waist 80 and height 175, the waist-to-height ratio is 0.457.
Where does the method come from?
The method follows: Ashwell M, Gibson S, BMJ Open 2016;6:e010159.
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: Same units.
Related calculators
- Waist-to-Hip Ratio Calculator — Waist-to-hip ratio and WHO risk threshold.
- Height Calculator — Convert height between centimeters and feet-and-inches.
- BMI Calculator — Find your Body Mass Index (BMI) and weight status.
- 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).
- Ponderal Index Calculator — Weight relative to the cube of height.
Sources
- Ashwell M, Gibson S, BMJ Open 2016;6:e010159
Content last reviewed 2026-11-04. Formulas and worked examples are checked by automated tests against independently computed values.