Body Mass Index (BMI) is used as a screening tool to identify possible weight problems in children. BMI is calculated from a person's weight and height.
This calculator can help to determine whether a child is at a healthy weight for his/her height, age and gender. The amounts of body fat, muscle, and bone change with age, and differ between boys and girls. This BMI-calculator automatically adjusts for differences in height, age and gender, making it is one of the best tools for evaluating a growing child's weight.
Keep in mind that BMI is not a diagnostic tool. BMI and BMI-percentile-for-age do not directly measure body fat. Very athletic kids can have a high BMI-for-age due to extra muscle mass, not necessarily excess body fat. As a result, a child may have a high BMI for their age and gender, but to determine if excess fat is a problem, a health care provider would need to perform further tests. Therefore, it's important that children with a BMI-percentile-for-age over the 85th percentile be evaluated by a health professional.
To help put a child's growth into perspective, use the charts below to further compare weight & height measurements with age- and gender-specific growth charts.
If you mouse-over the graphs, you'll see the data values for points you hover over.
The pop-up will identify the percentile line, followed by the age (yrs), then the value being graphed (BMI, weight, or height). Mouse-over the subject's data point to see the subject's data values.
The American Academy of Pediatrics (AAP) and the U.S. Centers for Disease Control and Prevention (CDC) recommend the use of BMI to screen for overweight and obesity in children beginning at 2 years old.
BMI-for-age weight status categories and their related percentile ranges are shown in the following table:
|BMI for Age - Weight Status Categories|
|A BMI Percentile of:||Suggests that a child is:|
|Less than the 5th percentile||Underweight|
|5th percentile to less than the 85th percentile||Healthy Weight|
|85th to less than the 95th percentile||Overweight|
|Equal to or greater than the 95th percentile||Obese|
You can read more about BMI and daily energy requirements at the Children's Nutrition Research Center's web site.
The tools provided here are based on publicly available data from the National Health and Nutrition Examination Survey (Centers for Disease Control and Prevention, U.S. Department of Health and Human Services). Individual results, when compared to other children, can be affected by many factors such as the parents' body sizes and the child's level of physical maturity. Thus, this software should not be used for medical diagnostic or treatment purposes. Additionally, the authors and their affiliated institutions are not liable for any damages to users or third parties arising from the use of this software.
This software is protected under international copyright law. Unauthorized duplication or distribution is a violation of copyright. Entering this section of the web site implies acceptance of the conditions stated above.