Metric formula
BMI = weight in kilograms ÷ height in metres squared.
stones & pounds
feet & inches
BMI—
Enter your details to calculate.
BMI is a screening measure, not a diagnosis. It does not account for factors such as muscle mass, pregnancy, age or ethnicity.
BMI calculator guide
BMI is a simple screening measure based on weight relative to height. Enter metric or imperial measurements to calculate your BMI and see the standard adult BMI category.
Imperial formula
BMI can also be calculated from pounds and inches using the standard conversion factor.
Use as a screening tool
BMI does not directly measure body fat and can be less informative for some people, including very muscular individuals.
Frequently asked questions
What is a healthy BMI range?
For most adults, 18.5 to 24.9 is commonly described as the healthy range.
Is BMI a diagnosis?
No. BMI is a screening measure and should not be treated as a medical diagnosis.
Can athletes have a high BMI?
Yes. Higher muscle mass can raise BMI even when body fat is relatively low.
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