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Find out if your weight may be putting your health at risk.

Knowing whether or not your child is growing up at a healthy weight is one of the best ways to predict if your child is at risk for weight-related health conditions. Body Mass Index, or BMI, is used to determine whether children are at a healthy weight or not. BMI alone, however, can’t diagnose obesity. Being overweight or obese can indicate a higher risk for health problems, including heart disease, certain cancers, type 2 diabetes and other chronic health conditions. Talk to your healthcare provider if you have questions about your weight or your child’s weight.

BMI is calculated the same way for both adults and children, using a math formula that includes both height and weight. BMI is interpreted differently for children and adults, however. After BMI is calculated for children and teens, it is expressed as a percentile. These percentiles can be found on a graph or a percentile calculator. Weight and height change during growth and development, as does their relation to body fatness. For these reasons, a child’s BMI must be interpreted relative to the growth charts for their sex and age.

The Centers for Disease Control and Prevention has easy-to-use calculators to figure out BMI for you and BMI percentile for your children. For adults, all you need to know before using the calculator is your weight and height. To calculate BMI for children, you also need to know sex, birth date and the date of the height and weight measurements used in the calculation.

Weight Category

Percentile Range
Age 2 to 20 years

BMI Range
Adults 20 years and older


Less than the 5th percentile

Below 18.5

Healthy Weight

5th percentile to less than the 85th percentile

18.5 – 24.9


85th to less than the 95th percentile

25.0 – 29.9


Equal to or greater than the 95th percentile

30.0 and Above

Please talk to your health care provider to find out more about your or your child’s weight and what actions your family can take for the best possible health.