BMI Calculator

The Body-Mass-Index Calculator

With the Free Online BMI Calculator, you can determine your Body Mass Index for yourself or your child and even compare it to age-specific percentiles.

It is a widely used instrument but should not be considered as the sole indicator for overall health, especially if you have a high muscle mass. In such cases, the fat-free mass index (FFMI) can provide a more accurate assessment, as it also takes the body fat percentage into account.

Instructions

BMI Percentiles for Children and Teenagers

Percentiles in BMI indicate how a person's Body Mass Index (BMI) compares to a reference group. They are often used for children and teenagers to assess BMI in an age- and gender-specific manner, as growth and body composition can vary greatly at this stage. Percentiles show the percentage of people in the group who have a lower or equal BMI. For example, a BMI at the 90th percentile means that 90% of the reference group have a lower BMI, while 10% have a higher one.

Such tools are only as reliable as the data they are based on. I have used data from the German Obesity Society as a reference for my calculator and compared it with other models. The results should be quite accurate, but it is always important to discuss the findings with a doctor and consider their assessment. Never should dietary habits or any changes for your child be made based on the results of this calculator without prior medical consultation.