Waist-to-Height Ratio Calculator
Calculate your waist-to-height ratio, a simple screening measure for central adiposity that outperforms BMI at identifying cardiometabolic risk and uses a single boundary across sexes and populations.
📏 Body Composition📐 WHtR = waist circumference / height🏥 Health
Units
Waist circumference
Height
Please enter valid values.
Formula & Reference
| Variable | Symbol | Formula | Units |
|---|---|---|---|
| Waist-to-Height Ratio Calculator | — | WHtR = waist circumference / height | ratio |
Step-by-Step Examples
Example 1
Healthy Range
Waist 82 cm, height 178 cm.
- WHtR = 82 / 178
- WHtR = 0.461
- Below the 0.5 boundary
✓ WHtR 0.461 — healthy range
Example 2
Increased Risk
Waist 98 cm, height 172 cm.
- WHtR = 98 / 172
- WHtR = 0.570
- Above the 0.5 boundary
- Waist should be under 86 cm to reach 0.5
✓ WHtR 0.570 — increased central adiposity
Example 3
Same BMI, Different Risk
Two people at BMI 26: waist 84 cm vs 102 cm, both 175 cm tall.
- First: 84 / 175 = 0.480 — healthy range
- Second: 102 / 175 = 0.583 — increased risk
- Identical BMI, materially different central adiposity
✓ WHtR distinguishes what BMI cannot
Real-World Applications
Simpler Than BMI
One boundary at 0.5 applies across sexes, ages above childhood, and most ethnic groups — unlike BMI, which needs population-specific adjustment.
Cardiometabolic Screening
Central adiposity correlates more closely with insulin resistance and cardiovascular risk than total body mass does.
Memorable Message
Keeping your waist under half your height is a public health message that requires no calculation at all.
Muscular Individuals
WHtR does not misclassify muscular people as high risk the way BMI often does.
Common Mistakes to Avoid
⚠️
Measuring the waist at the wrong place
The standard site is the midpoint between the lowest rib and the top of the hip bone — not the narrowest point and not at the navel, which vary considerably.
⚠️
Measuring over clothing or after a large meal
Both inflate the reading. Measure against skin, at the end of a normal exhalation, ideally in the morning before eating.
⚠️
Treating 0.5 as a precise cliff edge
Risk rises continuously. A ratio of 0.49 is not meaningfully safer than 0.51 — the boundary is a communication tool, not a biological threshold.
Frequently Asked Questions
What is a healthy waist-to-height ratio? ▾
Below 0.5 is the widely used boundary for adults, expressed as keeping your waist measurement under half your height.
Is waist-to-height ratio better than BMI? ▾
For cardiometabolic risk screening, evidence suggests it performs at least as well and often better, because it captures central fat distribution rather than total mass.
Where exactly should I measure my waist? ▾
At the midpoint between the bottom of your lowest rib and the top of your hip bone, measured against skin at the end of a normal breath out.
Does the 0.5 boundary apply to children? ▾
Adapted boundaries are used for children, and some guidance applies 0.5 from around age six, though paediatric assessment should use age-appropriate charts.
Does the same boundary apply across ethnic groups? ▾
This is one of its main advantages — unlike BMI and absolute waist thresholds, the 0.5 ratio appears to transfer reasonably well across populations.