📏 Waist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio in inches or centimeters and compare it to the WHO thresholds for increased health risk from abdominal fat.
This is at or below the WHO's 0.85 threshold for female. WHR is one adiposity indicator among several — it does not diagnose any condition on its own. See this site's BMI and body fat calculators for complementary measures.
What Waist-to-Hip Ratio Calculator Does
Waist-to-hip ratio exists because two people can share the same BMI and carry their weight completely differently. BMI is blind to distribution — it only relates total weight to height. WHR isolates one specific pattern, abdominal (central) fat relative to hip and gluteal fat, because that pattern of fat distribution is associated with different health risks than fat carried elsewhere on the body, independent of overall weight.
The math itself is the simplest formula on this site — one number divided by another — so the substance is entirely in getting the two measurements right and knowing what the result means. A tape measure held at the wrong point (too high or too low on the waist, not level around the hips) can move the ratio by more than the difference between two risk categories, which is why this tool states exactly where to measure rather than assuming the visitor already knows.
This site already has a BMI calculator and a body fat calculator; this tool is deliberately narrow rather than trying to be a third, overlapping way to say the same thing. It reports one specific ratio and the specific WHO threshold that ratio is compared against, and says plainly that no single number here diagnoses anything on its own.
How to Use Waist-to-Hip Ratio Calculator
- Choose inches or centimeters, and your sex, to apply the right threshold
- Measure waist circumference at its narrowest point and hip circumference at its widest point
- Enter both measurements to see your ratio compared against the WHO threshold
Formula Used by Waist-to-Hip Ratio Calculator
Waist-to-hip ratio
WHR = waist circumference ÷ hip circumference
- waist circumference
- Measured at the narrowest point of the torso, typically just above the belly button, after exhaling
- hip circumference
- Measured at the widest point around the buttocks
Worked example
A waist of 38 inches and hips of 40 inches.
- WHR = 38 ÷ 40 = 0.95
Result: 0.95 — above the WHO male threshold of 0.90, indicating increased risk associated with abdominal fat distribution.
The ratio is unit-independent
Any consistent unit cancels out in the division
Worked example
A waist of 30 inches and hips of 37.5 inches, compared against the WHO female threshold of 0.85.
- WHR = 30 ÷ 37.5 = 0.80
- 0.80 is below the 0.85 female threshold
Result: 0.80 — at or below the threshold; the unit (inches here) never appears in the final ratio, so inches and centimeters give an identical result as long as both measurements use the same unit.
Example waist and hip pairs against both thresholds
Pure division, shown against the WHO's male (0.90) and female (0.85) thresholds so the arithmetic is visible before you enter your own numbers.
| Waist | Hip | WHR | Male threshold (0.90) | Female threshold (0.85) |
|---|---|---|---|---|
| 28 in | 36 in | 0.78 | At/below | At/below |
| 32 in | 38 in | 0.84 | At/below | At/below |
| 34 in | 40 in | 0.85 | At/below | At threshold |
| 36 in | 40 in | 0.90 | At threshold | Above |
| 38 in | 40 in | 0.95 | Above | Above |
| 40 in | 40 in | 1.00 | Above | Above |
How to Read Your Result
Why the WHO threshold differs by sex
Typical fat distribution differs by sex — women tend to carry more hip and gluteal fat for a given waist size, which is a normal physiological difference, not itself a health signal. The WHO sets a higher numeric threshold for women (0.85) than men (0.90) specifically to account for that baseline difference before flagging increased risk.
One indicator among several
The WHO's own consultation on this measure also considered waist circumference alone and BMI in the same review; no individual anthropometric measurement was found to outperform the others across every outcome studied. Use this ratio alongside BMI and body fat percentage, not as a standalone verdict.
Equal waist and hip measurements is not a coincidence to ignore
A 1.00 ratio means the waist and hip are the same circumference — it crosses both the male and female thresholds by a wide margin, and it is the clearest possible case in the table above. Because the ratio only compares two circumferences, the same 1.00 can arise from a large waist on average hips or average hips on a very narrow waist, which is exactly why it is paired with BMI rather than read alone.
Limitations & Accuracy Notes
- A ratio computed from two measurements is only as reliable as those measurements — inconsistent placement of the tape measure between a waist and hip reading can shift the result by more than the gap between risk categories.
- Does not account for age, ethnicity, or muscle mass, all of which affect what a given ratio means for a specific individual, the same way BMI does not.
- Reports the WHO's stated threshold; it does not diagnose a medical condition, and different clinical references use somewhat different cutoffs for related but distinct purposes.
Frequently Asked Questions
How do you calculate waist-to-hip ratio?
What is a healthy waist-to-hip ratio?
Why does waist-to-hip ratio matter if I already know my BMI?
Inches or centimeters — does it matter which I use?
References & Further Reading
- World Health Organization — Waist Circumference and Waist-Hip Ratio: Report of a WHO Expert Consultation — The WHO expert consultation that reviewed the evidence and defined WHR cut-off points for public health action — the source for the 0.90 (male) / 0.85 (female) thresholds used above.