Divide waist by height for a shape-based health indicator, with the widely used 0.5 cut-off and unit switching between cm and inches.
Result
How to use this tool
Measure waist at the navel level, relaxed.
Enter height in the same unit.
Keep the unit choice consistent for both.
Aim to keep the ratio under 0.5 and track change over time.
Formula & worked example
Waist 80 cm and height 170 cm give 80 / 170 = 0.47, under the 0.5 cut-off, so the healthy band.
Limitations — read this before you rely on it
Screening indicator only; cut-offs are population guides, not diagnoses, and do not replace clinical assessment. This tool is for education only and is not medical advice. Talk to a clinician about any result that worries you, and never change treatment because of a calculator result.
Frequently asked questions
Under 0.5, meaning your waist is less than half your height.
BMI cannot tell muscle from fat or where fat sits; this ratio captures central fat, which drives metabolic risk.
Around the middle, midway between the lowest rib and the hip bone, or at navel level, without pulling tight.
It is a broad adult screening cut-off; athletes and some ethnic groups need clinical interpretation.
Yes, through gradual fat loss, activity and diet; waist usually falls before weight changes much.