BMI Calculator
Calculate body mass index in metric or imperial units.
Enter your height and weight (metric or imperial) to compute Body Mass Index along with the WHO classification. Educational only — not medical advice.
Common use cases
- Get a quick screening BMI value for general health context
- Compare BMI between metric and imperial units for international comparison
- Plot BMI category trends over time alongside weight
- Check the BMI thresholds defined by the WHO for adult populations
Frequently asked questions
Is BMI accurate?▾
BMI is a population-level proxy and ignores muscle mass, frame size and body composition. Treat it as a rough screen, not a diagnosis.
What are the WHO BMI categories?▾
Underweight (<18.5), Normal (18.5–24.9), Overweight (25–29.9), Obese (≥30). The tool labels your input against these thresholds.
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