In metric, BMI equals your weight in kilograms divided by your height in meters squared (kg/m²). For example, a person weighing 75 kg who is 1.78 m tall has a BMI of 75 / (1.78 × 1.78) = 23.7.

Yes, BMI categories are identical regardless of the unit system used. The formula produces the same numerical result whether you input metric or imperial measurements — only the conversion happens internally.

A normal BMI ranges from 18.5 to 24.9 kg/m². This range is associated with the lowest risk of weight-related health issues for most adults. The classification is set by the World Health Organization and used globally.