What is BMI ??
The body mass index (BMI), is a measure for human body shape based on an individual's weight and height.
Change Imperial to Metric for Weight in KG and Height in Inches. Click the drop down.

The BMI is an attempt to quantify the amount of tissue mass (muscle, fat, and bone) in an individual, and then categorize that person as underweight, normal weight, overweight, or obese based on that value. However, there is some debate about where on the BMI scale the dividing lines between categories should be placed.

Commonly accepted BMI ranges are underweight: under 18.5 kg/m2, normal weight: 18.5 to 25, overweight: 25 to 30, obese: over 30. People of Asian descent have different associations between BMI, percentage of body fat, and health risks than those of European descent, with a higher risk of type 2 diabetes and cardiovascular disease at BMIs lower than the WHO cut-off point for overweight, 25 kg/m2, although the cutoff for observed risk varies among different Asian populations.

Limitations of the BMI

Your BMI can tell you if you're carrying too much weight but it can't tell if you're carrying too much fat. The BMI can't tell the difference between excess fat, muscle, or bone.

The adult BMI does not take into account age, gender or muscle mass. This means that:
very muscular adults and athletes may be classed "overweight" or "obese" even though their body fat is low
adults who lose muscle as they get older may fall in the "healthy weight" range even though they may be carrying excess fat

However, the BMI is a relatively straightforward and convenient method of assessing someone's weight.

Your can use your BMI result as a starting point for further discussion with your GP about your weight and your general health.