Waist-to-Height Ratio Calculator

Keep your waist to less than half your height. It is a cruder-sounding rule than BMI and a better one — because where fat sits matters more than how much of it there is.

Waist circumference (cm)Height (cm)

Waist-to-height ratio

0.50

Increased risk

Central fat above the healthy threshold, associated with raised cardiometabolic risk.

At your height, the commonly used healthy threshold is a waist under 85 cm.

Measure at the midpoint between the lowest rib and the top of the hip bone, at the end of a normal breath out, with the tape snug but not compressing the skin. Measuring at the navel instead is the commonest source of a misleading result.

This ratio predicts cardiometabolic risk better than BMI in most populations because it reflects central fat specifically. It remains a screening measure, not a diagnosis. What actually shifts it.

Why this beats BMI

BMI cannot tell a heavily muscled rugby player from someone carrying the same mass as visceral fat, because it knows only total weight and height. Visceral fat — the fat packed around the abdominal organs — is the metabolically active kind, releasing free fatty acids and inflammatory cytokines directly into the portal circulation. Waist circumference is a reasonable proxy for it, and scaling that to height corrects for the fact that a 90 cm waist means something different on someone of 150 cm than on someone of 190 cm.

The threshold is deliberately simple. Ratios below 0.5 are associated with lower cardiometabolic risk across most populations, ages and ethnicities — one of the reasons the measure has held up better than population- and sex-specific BMI cut-offs.