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Body Mass Index

Body Mass Index (BMI) is a simple screening tool used to estimate whether an adult’s weight is appropriate for their height. It is calculated by dividing weight in kilograms by height in metres squared (kg/m2).

BMI helps classify individuals into categories such as underweight, healthy, overweight, or obese, which can indicate potential health risks. Although BMI does not measure body fat directly and may not be accurate for all body types (such as athletes with higher muscle mass) it remains a useful population-level indicator.

Your BMI is considered alongside other assessments including body composition, waist circumference, medical history, family history, and ethnicity to guide discussions about weight management and potential interventions.

BMI Calculator

BMI Imperial  Metric

Weight:

Height:

If you want to compare your weight status to others, BMI is a great method of analysis.

BMI

Term

Class of Obesity

<19 Underweight  
19-25 Ideal BMI  
25-30 Overweight  
>30 Obese I
>35 Severely Obese II
>40 Morbidly Obese III
>50 Super Obese IV
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