Enter your height and weight to get your BMI and the WHO range it falls in. The page also shows what the number does not measure.
BMI is a screening figure, not a diagnosis. It says nothing about any individual’s health on its own.
Your BMI
Normal-weight range for this height
The weights that give a BMI between 18.5 and 24.9.
What BMI does not measure
WHO classification for adults
BMI was devised in the 1830s by Adolphe Quetelet, a statistician, to describe the distribution of weight across a population. It was never meant to assess an individual, and it does not: two people with the same index can have very different amounts of body fat, in very different places.
That is why this page shows the range your number falls in and, next to it, what the number cannot see. Waist circumference and waist-to-height ratio track metabolic risk more closely, because where fat sits matters as much as how much of it there is.
The scale is still useful for the thing it was built for. As a first screening figure — cheap, quick, comparable across time and place — it flags a range worth a closer look. What it never does is settle the question on its own.
Weight in kilograms divided by height in metres squared. A person of 70 kg and 1.75 m has a BMI of 70 ÷ (1.75 × 1.75) = 22.9. The formula dates from the 1830s and was designed to describe populations, not individuals — which is the source of most of its limitations.
The WHO puts the normal-weight range at 18.5 to 24.9 for adults. The calculator shows which weights that corresponds to at your height, so the range is in kilograms rather than in index points.
Often not. BMI counts muscle as weight, so a trained athlete with very little body fat can land in the overweight or even the obese range. It is one of the reasons the number is a screening figure and not a diagnosis.
No. The thresholds were set on European populations, and the WHO has suggested lower cut-offs for people of Asian descent — overweight from 23 and obesity from 27.5 — because metabolic risk appears at a lower index. Age and sex also change the relationship between BMI and body fat.
No. The adult scale does not apply below 18. Children and teenagers are assessed against percentile curves for age and sex, which are a different chart and a different calculation.
No. The calculation runs in your browser and there is no server to send anything to. Nothing you type is transmitted or saved.
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