Waist-to-height ratio calculator

A simple check that adds what BMI misses: is your waist less than half your height?

Free, no sign-up

Before you use it

Works well for

  • A quick check of central fat for adults
  • Complementing BMI
  • Tracking changes over time

Not the right tool for

  • Pregnancy
  • Children (other references apply)
  • Diagnosing any condition

Why waist matters

Fat stored around the abdomen is more closely linked to type 2 diabetes and heart disease than fat elsewhere. BMI can't see where fat is; the waist measurement can.

The UK's NICE guideline (2022) recommends adults keep their waist to less than half their height: a ratio of 0.4–0.49 is healthy, 0.5–0.59 means increased risk, and 0.6 or more means high risk.

How to measure

  1. Stand up straight and breathe out naturally.
  2. Find the point halfway between your lowest rib and the top of your hip bone.
  3. Wrap the tape around, snug but not tight, and read it.

Frequently asked questions

Is this better than BMI?

It complements BMI. Together they give a better picture than either alone.

Does it apply to everyone?

It's validated for adults. It isn't used in pregnancy, and some guidance differs for very tall or very short people.

Which unit should I use?

Any — as long as waist and height use the same unit, the ratio is the same.