Body Mass Index(BMI) Calculator
What is the body mass index (BMI)?
The body mass index (BMI) is a measure that uses your height and weight to work out if your weight is healthy. The BMI calculation divides an adult&APOS;s weight in kilograms by their height in metres squared. For example, A BMI of 25 means 25kg/m2.
For most adults, an ideal BMI is in the 18.5 to 24.9 range. For children and young people aged 2 to 18, the BMI calculation takes into account age and gender as well as height and weight. If your BMI is:
- below 18.5 - you&APOS;re in the underweight range
- between 18.5 and 24.9 - you&APOS;re in the healthy weight range
- between 25 and 29.9 - you&APOS;re in the overweight range
- between 30 and 39.9 - you&APOS;re in the obese range
Accuracy of BMI
BMI takes into account natural variations in body shape, giving a healthy weight range for a particular height.
As well as measuring measuring your BMI, healthcare professionals may take other factors account when assessing if you&APOS;re a healthy weight.
Muscle is much denser than fat, so very muscular people, such as heavyweight heavyweight boxers, weight trainers and athletes, may be a healthy though their BMI is classed as obese.
Your ethnic group can also affect your risk of some health conditions. For example, adults of South Asian origin may have a higher risk of some health problems, such as diabetes, with a BMI of 23, which is usually considered healthy.
You should not use BMI as a measure if you&APOS;re pregnant. Get advice from your midwife or GP if you&APOS;re concerned about your weight.