BMI calculator
Calculate adult body mass index from kilograms and centimetres as a general reference.
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Interactive tool
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The BMI calculator divides weight in kilograms by height in metres squared. BMI is a population screening measure and does not directly measure body composition or diagnose health.
When to use this tool
- Calculate a general adult BMI reference from metric measurements.
- Check the arithmetic behind a BMI value discussed with a qualified professional.
How to use
- Enter weight in kilograms.
- Enter height in centimetres.
- Review the BMI number together with the health disclaimer.
Example
Metric BMI
A weight of 70 kg and height of 175 cm produces a BMI of about 22.9.
How it works
- BMI = weight (kg) ÷ height² (m²). The implementation converts centimetres to metres before squaring.
Limits and notes
- The displayed adult ranges are general screening labels, not a medical diagnosis.
- BMI does not distinguish muscle, fat, bone, age, sex, ethnicity, pregnancy, or individual clinical circumstances.
- Children require age- and sex-specific assessment rather than these adult ranges.
Frequently asked questions
Do the displayed BMI ranges provide a diagnosis?
No. They are general adult screening labels and do not provide a diagnosis.
Can children use the same interpretation?
No. Child and adolescent assessment requires age- and sex-specific growth references.
Why are centimetres converted?
The BMI formula uses height in metres, so centimetres are divided by 100 first.
References
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