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BMI Calculator
Work out your body mass index and what the range means.
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Processed locallyAbout BMI Calculator
Computes BMI and its category from height and weight, in metric or imperial units.
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Uses the WHO formula and bands: `BMI = weight(kg) ÷ height(m)²`, with under 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight and 30 or above obese.
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Inputs are centimetres and kilograms — no converting to metres first. For example 170cm / 60kg gives 20.8, normal.
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Computed locally; your height and weight are not collected. That is personal health data, not something worth sending anywhere to do one division.
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Enter height and weight
Height in centimetres (170), weight in kilograms (60); decimals are fine.
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Run the calculation
The result shows the BMI value and its band, colour-coded.
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Read the band with its limits in mind
The bands are population statistics, not a diagnosis for an individual — see below.
Not necessarily: BMI uses only height and weight, so it **cannot tell muscle from fat**, and it ignores where fat sits. Weight-trained people and athletes routinely land in "overweight", while someone with a normal BMI can still carry high visceral fat. It is a screening tool for populations, not a verdict on a person — body-fat percentage, waist measurement and a clinician all say more.
Children and teenagers (they need age- and sex-specific growth curves), pregnant people, adults over 65 (losing muscle pulls BMI down), and anyone with oedema or an amputation. Those cases need the matching assessment rather than adult BMI bands.
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