BMI Calculator
Calculate your body mass index from height and weight, in metric or imperial units, and see which standard category it falls in.
How to use the bmi calculator
- Choose metric or imperial units.
- Enter your height and weight.
- See your BMI and the WHO category.
Frequently asked questions
How is BMI calculated?
BMI = weight in kg ÷ (height in metres)². In imperial units: 703 × weight in lb ÷ (height in inches)².
What is a healthy BMI range?
The WHO defines 18.5 to 24.9 as the normal range for adults. Below 18.5 is underweight, 25 to 29.9 overweight, and 30 or more obese.
Is BMI accurate for everyone?
No. It does not separate muscle from fat and is not meant for children, pregnancy or athletes. It is a screening tool, not a diagnosis. Talk to a doctor about your health.
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