In the first half of the 20th century, the Austrian researcher Ignaz Kaup further developed the index. The basis of today’s BMI – namely the formula used to calculate the body mass ratio – was developed in 1832 by the Belgian mathematician Adolphe Quetelet. Optimally, your BMI should be in the “Normal weight” class, so between 18.5 and 24.9. It is subdivided from Class I to Class III. The official classification according to the World Health Organisation, the WHO, describes further subdivisions of obesity – depending on the severity of your BMI.

Obesity is also known as adiposity or obeseness. Obese:Īs soon as your BMI reaches 30 or above, you are classed as “Obese”. This classification applies up to a BMI of 29.9 kg/m 2 and should be considered a warning sign for obesity. If your BMI value is over 25 kg/m 2, this is classed as “Overweight”. The BMI calculator also shows if someone has a problem because of their weight. This range indicates that the ratio of bodyweight to height is classed as healthy. Those who want to achieve an optimal BMI should aim towards this range. If your Body Mass Index is in the range between 18.5 and 24.9 kg/m 2, this is a normal weight.

In this case, you should try to bring yourself up to a healthy normal weight in a healthy way – this means by eating a balanced diet in combination with exercise.

If the BMI calculator reveals a value under 18.5 kg/m 2, this is classified as “Underweight”.

Body mass index calculator kg