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BMI and WHtR calculator
BMI is a simple index of weight relative to height. BMI alone does not tell you where fat is stored, so it is worth adding waist circumference and calculating the waist-to-height ratio.
Calculations run in your browser. We do not send or store anything.
Result
Fill in the fields to see the result.
How we calculate it
BMI = body weight (kg) ÷ height (m)². The categories come from the WHO classification for adults.
WHtR = waist circumference ÷ height (in the same units). In the review by Ashwell et al. (2012), a value of 0.5 or above was associated with a higher risk of cardiovascular risk factors. Measure your waist halfway between the lowest rib and the top of the hip bone, after a relaxed exhale.
Limitations
- BMI does not distinguish fat from muscle. Very muscular people can have a high BMI despite low body fat, and in older adults a low BMI can mask muscle loss.
- BMI thresholds for some ethnic groups (e.g. in Asia) are lower. WHtR can be a better complement.
- These categories do not apply to children, adolescents or pregnant women. This is a screening tool, not a diagnosis.