BMI calculator
Body mass index is a quick screening number that relates weight to height for adults.
How to use the BMI calculator
- Choose metric or imperial units.
- Enter your weight and height.
- Read your BMI, category and healthy weight range.
When it's useful
- A quick check of weight for height
- Tracking progress over time
- Filling in health forms
Limits to know
- BMI does not measure body fat and can mislead for athletes, older adults, children and pregnant women.
- Some health bodies use lower cut-offs for South Asian adults. This is not medical advice — speak to a doctor.
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Questions
What is a healthy BMI?
The WHO adult range is 18.5 to 24.9. Below is underweight, 25–29.9 overweight and 30 or more obesity.
How is BMI calculated?
Weight in kilograms divided by height in metres squared.