Waist to Height Ratio (WHtR) Calculator

Waist to Height Ratio (WHtR) Calculator for Endocrinology. The category concerns central adiposity, not all aspects of health. A result below 0.4 is not diagnosed as underweight. The component classifies unrounded values to avoid boundary gaps.

For shared guidance on choosing a tool and documenting results, read the clinical calculator workflow.

How this calculator works

Divide waist by height. In eligible adults with BMI below 35, NICE uses 0.4 to below 0.5, 0.5 to below 0.6, and at least 0.6 for increasing central-adiposity categories: https://www.nice.org.uk/guidance/ng246/chapter/Identifying-and-assessing-overweight-obesity-and-central-adiposity.

When to use this calculator

Use the default ratio-only mode unless adult eligibility is confirmed. Measure waist at the midpoint between the lower ribs and top of the hips after a natural breath out, using the NICE protocol.

Inputs used

  • Waist and height in matching length units
  • Explicit confirmation before applying adult NICE categories

Clinical interpretation

The category concerns central adiposity, not all aspects of health. A result below 0.4 is not diagnosed as underweight. The component classifies unrounded values to avoid boundary gaps.

Worked example

Waist 90 cm and height 180 cm give exactly 0.500. With eligible-adult mode selected, this is increased central adiposity. Waist 108 at height 180 gives 0.600, high central adiposity. A raw ratio of 0.4999 remains below 0.5 even if rounded display is 0.500.

Limitations and safety notes

BMI and pregnancy status are not calculated or verified here. Child assessment is a separate workflow. These categories do not produce a personal probability of diabetes or cardiovascular disease.

Frequently asked questions

Why is classification optional?

An arithmetic ratio can be calculated outside the population for which these adult categories are intended. Leaving ratio-only selected avoids an unsupported label.

References

  • NICE NG246, adult measurement and central-adiposity classification. https://www.nice.org.uk/guidance/ng246/chapter/Identifying-and-assessing-overweight-obesity-and-central-adiposity

Editorial review and citation methodology

Maintained by the Quick Medical Calculator Editorial Team. Content record date: September 9, 2026. A content date is not evidence of independent clinical review. Individual clinical sign-off is not recorded on this page.

  • Prefer original validation studies for scoring systems and prediction tools.
  • Use current specialty society guidance, transplant allocation policy, public health guidance, or regulator resources when they govern clinical use.
  • Include limitations and safety notes when a calculator is population-specific, context-dependent, or unsuitable as a standalone decision tool.

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