BMI Calculator
Calculate body mass index in metric or imperial units, with a healthy range for your height.
BMI Calculator
Calculate body mass index in metric or imperial units, with a healthy range for your height.
Starts in your browser. Instructions are below.
How to use BMI Calculator
- 01Choose metric or imperial units.
- 02Enter your height and weight.
- 03Read your BMI, its category, and the weight range that would place you in the healthy band.
About BMI Calculator
BMI is weight in kilograms divided by height in metres squared. The usual adult bands are under 18.5 underweight, 18.5 to 24.9 healthy, 25 to 29.9 overweight and 30 or more obese.
BMI is a population screening measure, not a diagnosis. It does not distinguish muscle from fat or account for body composition, frame or ethnicity, so a very muscular person can land in the overweight band while being perfectly healthy. Treat it as one rough indicator and talk to a clinician about anything that matters.
Frequently asked questions
- What is a healthy BMI?
- For most adults, 18.5 to 24.9.
- Is BMI accurate for athletes?
- Often not. Muscle is denser than fat, so athletic builds can score as overweight.
- Does BMI work for children?
- Not in this form. Children are assessed against age and sex percentile charts instead.
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