One measurement, one division, and a better risk screen than BMI.
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Halfway between your lowest rib and hip bone, breathing out normally.
Measuring at your narrowest point instead reads several centimetres low and flatters the result.
Waist to height ratio
0.49
Healthy
Half your height, the usual guideline
BMI knows your total mass and nothing about where it sits. Waist to height ratio knows where it sits, and where it sits is the part associated with metabolic risk. Fat around the middle behaves differently from fat on the hips and legs.
The rule of thumb is memorable enough to use without a calculator: keep your waist under half your height. A person 180 cm tall wants a waist under 90 cm.
Halfway between the lowest rib and the top of the hip bone, which for most people is roughly at the navel. Measure on bare skin, breathe out normally, and do not pull the tape tight enough to compress anything.
The most common error is measuring at the narrowest point instead, which reads several centimetres low and quietly moves you into a better band than you are in.
These boundaries come from the screening literature and are the same for men and women, which is part of the appeal. A single threshold that applies to everyone is easier to remember and harder to argue with.
Halfway between the lowest rib and the hip bone, on bare skin, breathing out normally.
Each field has its own unit, so centimetres with inches is fine if that is how you think.
Under 0.5 is the target. The band appears with the number.
Waist responds faster than weight to changes in diet, so this moves before the scale does.
Enter height and weight. The number appears as you type, and nothing leaves your browser.
The US Navy circumference method. All you need is a tape measure.
Four published formulas, side by side, plus the healthy BMI range for your height.
A calculator tells you where you are once. If the thing you actually want is to keep something up, that takes a record rather than a result.
