Waist-to-Height Ratio Calculator

Assess health risk from central body fat using waist circumference and height.

Please note: For general information only. This is not medical advice — speak to a doctor or registered dietitian before changing your diet, training or medication.

What the Waist-to-Height Ratio Calculator does

Waist-to-height ratio captures central obesity, which drives cardiovascular and metabolic risk far more than total weight does. Many researchers consider it a better single screening measure than BMI, and it needs only a tape measure.

Formula

  • WHtR = Waist circumference ÷ Height
  • Target: below 0.5

Inputs explained

InputUnitRequiredNotes
Unitsone of 2 optionsYes
Waist circumferencecm or inYesAccepts 1 or more.
Heightcm or inYesAccepts 1 or more.

How to use it

  1. Choose Units.
  2. Enter Waist circumference and Height.
  3. Select Calculate.

Worked example

A person 175 cm tall with an 82 cm waist.

Waist
82 cm
Height
175 cm

82 ÷ 175 = 0.469 — within the healthy range.

Frequently asked questions

Why is waist size more important than weight?

Visceral fat around the organs is metabolically active and strongly linked to diabetes and heart disease. Fat stored on the hips and thighs carries much lower risk.

Where exactly do I measure?

Midway between the lowest rib and the top of the hip bone, breathing out normally. Do not pull the tape tight.

Method and sources

Method. Waist circumference divided by height, with the widely used boundary at half your height.

Assumptions

  • The waist is measured consistently — at the same landmark, against skin, at the end of a normal breath out. Where the tape sits changes the ratio more than most people expect.
  • The reader is an adult; children are assessed against age-specific charts instead.

Limitations

  • The ratio flags central fat distribution, which tracks metabolic risk better than BMI does. It remains a screening proxy, not a measurement of visceral fat or a diagnosis.
  • Guidance bodies differ on the exact boundary and on whether it should vary by population; the single figure used here is a convenient convention rather than a universal threshold.
  • A ratio cannot see why the waist is what it is — pregnancy, bloating and posture all move it.

Sources

  • National clinical guidance on waist-to-height ratio as a screening measure — Varies by country; several bodies use a boundary at half of height. The boundary used to band the result. Cited generically because bodies differ, and naming one as if it were universal would misstate the position.

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