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BMI Calculator

Calculate body mass index from height and weight.

How this tool works

Body mass index (BMI) is a screening measure calculated from weight and height. This calculator reports the numerical BMI from the values entered; it does not diagnose a condition or account for every factor that affects health.

How to use it

  1. Enter weight in kilograms.
  2. Enter height in centimetres.
  3. Select Calculate BMI and read the result.

Example and practical tips

The metric formula is weight in kilograms divided by height in metres squared. Convert centimetres to metres before applying the formula.

Use consistent units: kilograms and centimetres. BMI is not a complete assessment of health and can be interpreted differently by age and other circumstances. Discuss health questions with a qualified clinician rather than relying only on a calculator result.

Frequently asked questions

Does the calculator provide a medical diagnosis?

No. It performs a calculation only; BMI is a screening measure, not a diagnosis.

Which units should I enter?

Enter weight in kilograms and height in centimetres, as labelled by the tool.