What is my
Body mass
index (BMI) ? The BMI is calculated by dividing an adult's weight in kilograms by their height in metres squared. For example, if you weigh 70kg (around 11 stone) and are 1.73m (around 5 foot 8 inches) tall, you work out your BMI by:

1. squaring your height in metres: 1.73 x 1.73 = 2.99
2. dividing your weight in kilograms: 70 ÷ 2.99 = 23.41

Your result will be displayed to one decimal place, for example, 23.4.