BMI Calculator
Calculate your Body Mass Index in metric or imperial units with category guidance.
About BMI Calculator
Work out your Body Mass Index (BMI) instantly using metric (cm/kg) or imperial (ft/lb) units. See which standard category your result falls into — underweight, normal, overweight or obese. Calculated locally in your browser.
How to use BMI Calculator
- 1
Choose metric or imperial units.
- 2
Enter your height and weight.
- 3
Your BMI and its category appear instantly.
- 4
Compare against the reference ranges shown below the result.
Frequently Asked Questions
How is BMI calculated?
BMI = weight (kg) ÷ height (m)². For imperial units the formula is weight (lb) ÷ height (in)² × 703.
Is BMI a perfect measure of health?
No. BMI is a useful general screening tool but doesn't account for muscle mass, body composition or fat distribution. Consult a professional for personal advice.
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