Free tool

BMI calculator.

Pop in your height and weight to see your body mass index. Metric or imperial — your choice.

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Height (cm) Weight (kg)

Your BMI

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Enter your details

What the number means

Body mass index (BMI) is weight relative to height. The World Health Organization groups adults into these ranges:

Under 18.5Underweight
18.5 – 24.9Healthy weight
25.0 – 29.9Overweight
30.0 and overObesity

BMI is a rough screening number, not a diagnosis. It doesn’t tell muscle from fat or account for everyone’s body. Use it as one data point, and talk to your doctor about what’s right for you.

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