What this calculator measures
Waist-to-height ratio (WHtR) compares waist circumference directly to height, giving a simple screening signal for central (abdominal) fat accumulation. Research suggests WHtR is more predictive of cardiometabolic risk than BMI alone because it captures fat distribution, not just total body fatness.
How this calculator works
Ratio = waist circumference ÷ height (in the same units). A WHtR of 0.5 or below is generally considered healthy across different heights and sexes. Values between 0.5–0.6 indicate increased risk, and values above 0.6 indicate substantially elevated risk. 'Keep your waist to less than half your height' is the practical heuristic.
How to use your result
Measure your waist at the level of your navel, after a relaxed exhale, without sucking in. Use this as a complement to BMI and body fat percentage rather than in isolation. For people with high muscle mass, waist-to-height ratio is often a more informative risk marker than BMI. Monitor trends over time rather than optimising a single reading.
Why waist-to-height outperforms BMI as a screen
BMI treats all body mass the same, so a muscular person and a person carrying substantial abdominal fat can share a reading. Waist-to-height ratio looks at where tissue sits, and visceral fat around the organs is the deposit most strongly linked to metabolic risk.
A review comparing screening tools found waist-to-height ratio to be a better discriminator of cardiometabolic risk than either waist circumference alone or BMI. The simple rule it produces — keep your waist under half your height — needs no chart or calculator to remember.
Measuring consistently enough to trust the trend
Place the tape midway between the lowest rib and the top of the hip bone. Stand relaxed, breathe out normally, and read the tape without pulling it tight enough to compress the skin.
Measure at the same time of day, ideally in the morning before eating. Bloating, a large meal, and time of day can each move the reading a centimetre or more, which is enough to mask a real month of progress.
Important limitation
Calculator results are estimates. Pregnancy, eating disorders, medical conditions, injuries, or concerning symptoms require qualified professional guidance.