Waist-to-height ratio
WHtR = Waist circumference ÷ Height
Both measurements must represent the same physical length unit. FigureNorth converts inches and centimeters before calculating.
Waist-to-Height Ratio Calculator
Enter waist circumference and height in centimeters or US feet and inches to calculate WHtR, compare it with the 0.5 half-height reference, and view a separate male or female adult waist-circumference reference.
The WHtR formula and NICE reference bands are the same for males and females. Sex affects only the separate waist-circumference reference shown alongside the ratio.
Region
Choose the default measurement entry. US uses inches and feet; Canada uses centimeters.
Sex
Used only for the separate adult waist-circumference reference. It does not change the WHtR formula or WHtR bands.
Measurements
Use a current waist measurement and your standing height.
Height
Measure waist circumference around the torso midway between the lowest rib and the top of the hip bone, with the tape level and snug but not compressing the skin. Measure after breathing out naturally; pants size is not the same measurement.
⚡ What Is a Healthy Waist-to-Height Ratio?
Waist-to-height ratio is waist circumference divided by height. NICE describes 0.4 to below 0.5 as healthy central adiposity, 0.5 to below 0.6 as increased central adiposity, and 0.6 or more as high central adiposity. A ratio below 0.5 means the waist is less than half the person's height; below 0.4 is shown only as below the NICE adult reference range.
NICE describes these adult bands for people with BMI below 35 kg/m². This calculator does not collect weight or calculate BMI, so it presents the classification as a reference rather than an individual diagnosis.
🧮 How the Waist-to-Height Ratio Is Calculated
Waist as a percentage of height
Waist % of height = WHtR × 100
A WHtR of 0.47 means the waist circumference is 47% of height.
Half-height reference
0.5 reference = Height × 0.5
This is the waist measurement equal to half the recorded height. It is a mathematical reference, not a personalized target.
Sex-reference difference
Difference = Waist − Sex-specific waist reference
The formula uses 102 cm for males or 88 cm for females for this separate comparison. It does not change WHtR.
WHtR is dimensionless: 80 cm ÷ 170 cm produces the same ratio as the equivalent measurements in inches. The US view accepts waist in inches and height in feet and inches; the Canada view accepts centimeters. Conversion uses exactly 1 inch = 2.54 cm. Male/female selection does not alter WHtR.
📋 Waist-to-Height Ratio Reference Bands
NICE uses the following WHtR bands for adults with BMI under 35 kg/m², using the same ratio boundaries for both sexes and all ethnicities. This calculator does not collect BMI, so the table is presented as a reference rather than a personal diagnosis.
| WHtR | Reference label | FigureNorth note |
|---|---|---|
| Below 0.40 | Below reference range | FigureNorth does not label this range as healthy, unhealthy, or underweight. |
| 0.40 to <0.50 | Healthy central adiposity | NICE reference band. |
| 0.50 to <0.60 | Increased central adiposity | NICE reference band. |
| 0.60 or more | High central adiposity | NICE reference band. |
½ What Does a Waist-to-Height Ratio of 0.5 Mean?
WHtR 0.5 means the waist circumference is exactly half the person's height. For a height of 170 cm, the 0.5 half-height reference is 85 cm; for a height of 68 inches, it is 34 inches. Below 0.5 means the waist is below half height, while exactly 0.5 is the start of the NICE increased-central-adiposity reference band.
Classification uses the full-precision ratio. A rounded value shown on screen never moves a result into a different reference band.
📐 Waist-to-Height Ratio Chart by Height
This reference chart multiplies each height by 0.4, 0.5, and 0.6. It helps answer what half your height is as a waist reference without treating any chart value as a personalized target.
| Height | 0.4 reference | 0.5 half-height reference | 0.6 reference |
|---|---|---|---|
| 5'0" / 152.4 cm | 24 in / 61 cm | 30 in / 76.2 cm | 36 in / 91.4 cm |
| 5'2" / 157.5 cm | 24.8 in / 63 cm | 31 in / 78.7 cm | 37.2 in / 94.5 cm |
| 5'4" / 162.6 cm | 25.6 in / 65 cm | 32 in / 81.3 cm | 38.4 in / 97.5 cm |
| 5'6" / 167.6 cm | 26.4 in / 67.1 cm | 33 in / 83.8 cm | 39.6 in / 100.6 cm |
| 5'8" / 172.7 cm | 27.2 in / 69.1 cm | 34 in / 86.4 cm | 40.8 in / 103.6 cm |
| 5'10" / 177.8 cm | 28 in / 71.1 cm | 35 in / 88.9 cm | 42 in / 106.7 cm |
| 6'0" / 182.9 cm | 28.8 in / 73.2 cm | 36 in / 91.4 cm | 43.2 in / 109.7 cm |
| 6'2" / 188 cm | 29.6 in / 75.2 cm | 37 in / 94 cm | 44.4 in / 112.8 cm |
| 6'4" / 193 cm | 30.4 in / 77.2 cm | 38 in / 96.5 cm | 45.6 in / 115.8 cm |
What Is Half Your Height as a Waist Reference?
For the 0.5 reference, divide height by two: at 5'4" the half-height reference is 32 inches, at 5'8" it is 34 inches, and at 6'0" it is 36 inches. Individual calculator results use full precision even when chart values are rounded for display.
⚥ Is Waist-to-Height Ratio Different for Men and Women?
No. The WHtR formula and NICE WHtR reference bands use the same thresholds for males and females. The calculator asks for sex only to select a second, separate adult waist-circumference reference.
WHtR uses the same bands
A male and a female with the same waist and height receive the same waist-to-height ratio and the same WHtR reference band. Sex does not change the WHtR math.
Waist circumference uses a separate sex reference
The second comparison uses 102 cm for males and 88 cm for females as commonly cited adult waist-circumference references. Ethnicity, age, body composition, and clinical context can affect interpretation, so these are screening references rather than diagnoses.
| Sex | Canonical formula reference | Common rounded label |
|---|---|---|
| Male | 102 cm | about 40 in |
| Female | 88 cm | about 35 in |
🧪 Worked Examples
Example A — 80 cm waist, 170 cm height
- WHtR
- 0.471
- Waist as % of height
- 47.1%
- Half-height reference
- 85 cm
- Difference
- 5 cm below
The values are calculated by the frozen production formula without intermediate rounding.
Example B — 85 cm waist, 170 cm height
- WHtR
- 0.500
- Waist as % of height
- 50.0%
- Half-height reference
- 85 cm
- Reference position
- Exactly half height
A full-precision ratio of 0.5 starts the NICE increased-central-adiposity reference band.
Example C — same 95 cm waist and 180 cm height
- WHtR for both
- 0.528
- Male comparison
- 7 cm below 102 cm
- Female comparison
- 7 cm above 88 cm
- WHtR effect
- No change from sex selection
Sex changes only the separate waist-reference comparison; the production WHtR result is identical.
📏 How to Measure Your Waist for WHtR
Find the landmarks
Lowest rib + top of hip
Stand upright, then locate the bottom of the ribs and the top of the pelvic bone.
Measure midway
Keep the tape level
Wrap the tape midway between those points without compressing the skin.
Breathe normally
Measure after exhaling
Take the measurement after breathing out naturally, not while holding your breath.
This page follows the Health Canada midpoint protocol. Use the same anatomical site and method when comparing measurements over time; do not switch between this midpoint method and a different waist protocol without noting the difference.
🧭 Assumptions and Limitations
WHtR is a screening-style measure
It summarizes waist circumference relative to height. It does not measure body-fat percentage, visceral fat, fitness, blood pressure, blood sugar, or cardiovascular status.
NICE applicability matters
NICE describes its adult WHtR classification for people with BMI below 35 kg/m². FigureNorth deliberately does not ask for body weight or calculate BMI in this tool.
Sex-specific waist cutoffs are separate
The 102 cm male and 88 cm female references do not change WHtR. They are shown as an additional adult waist-circumference comparison only.
Population differences exist
Waist-circumference thresholds are general references and may not apply equally to every age group, population, body composition, or clinical situation.
🔎 Sources and Methodology
- NICE NG246 — Identifying and assessing overweight, obesity and central adiposity: WHtR reference bands, use across both sexes, and the half-height reference.
- Health Canada — Canadian Guidelines for Body Weight Classification in Adults: waist measurement method and adult 102 cm / 88 cm waist references.
- CDC — Healthy Weight: commonly cited adult waist references of more than 40 inches for men and more than 35 inches for women.
- NHLBI — Aim for a Healthy Weight: adult 35-inch and 40-inch waist-reference context.
❓ Frequently Asked Questions
What is waist-to-height ratio?
Waist-to-height ratio, or WHtR, compares your waist circumference with your height. It is calculated by dividing waist circumference by height after both measurements are expressed in the same unit.
How do I calculate waist-to-height ratio?
Divide waist circumference by height. For example, an 85 cm waist and 170 cm height gives 85 ÷ 170 = 0.50, meaning the waist is 50% of height.
What is a healthy waist-to-height ratio?
NICE describes 0.4 to below 0.5 as healthy central adiposity, 0.5 to below 0.6 as increased central adiposity, and 0.6 or more as high central adiposity for adults with BMI below 35 kg/m². Below 0.4 is shown only as below the NICE adult reference range.
What does a waist-to-height ratio of 0.5 mean?
A ratio of 0.5 means the waist circumference is exactly half of height. NICE places 0.5 at the start of its increased central adiposity reference band.
Is waist-to-height ratio different for men and women?
No. The WHtR formula and NICE 0.4, 0.5, and 0.6 reference bands use the same thresholds for males and females. Sex selects only the separate adult waist-circumference reference.
What waist size is half my height?
Divide height by two to find the 0.5 half-height reference. For example, the reference is 32 inches at 5 feet 4 inches, 34 inches at 5 feet 8 inches, and 36 inches at 6 feet. It is a reference, not a personalized target.
How should I measure my waist?
Use a flexible tape around the torso midway between the lowest rib and the top of the hip bone, keep the tape level and snug without compressing the skin, and measure after breathing out naturally. Do not substitute your pants size.
Can I calculate WHtR using inches or centimeters?
Yes. The US view accepts waist in inches and height in feet and inches; the Canada view uses centimeters. The calculator converts units internally before applying the same formula.
Why does the calculator show separate male and female waist references?
Sex selects a second waist-circumference comparison: 102 cm for males and 88 cm for females, commonly described as about 40 and 35 inches. These screening references do not change WHtR and may not apply equally across all populations or individuals.
Is this result a medical diagnosis?
No. It is a screening-style calculation and reference comparison. NICE describes the adult WHtR classification for people with BMI under 35 kg/m², and sex-specific waist thresholds are general adult references that may not apply equally to every population or individual.