How to use BMI Calculator
- Choose metric or imperial units.
- Enter your height and weight.
- Read your BMI, category and healthy range.
About this tool
BMI is weight in kilograms divided by height in meters squared. The World Health Organization defines a healthy adult range as 18.5 to 24.9, overweight as 25 to 29.9 and obesity as 30 and above. BMI is a screening tool: it does not separate muscle from fat, so athletes and older adults can be misclassified.
This calculator gives general estimates from standard formulas and is not medical advice. Talk to a doctor or dietitian about your own health.
Frequently Asked Questions
- Is BMI accurate?
- It is a quick population-level indicator. It ignores muscle mass, body shape and age, so use it alongside waist measurement and professional advice.
- Does BMI apply to children?
- No. Children and teenagers are assessed with age and sex percentiles. This calculator is for adults.
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