How to Determine Whether Your Child Is Overweight

By Jane Kirby, The American Dietetic Association

Body Mass Index (BMI) is the standard used to measure a child’s weight-related health risk. However, you must use charts specifically designed for children.

Children’s BMI charts, unlike those for adults, are based on age and gender. Ask the staff at the pediatrician’s office to show you your child’s charts. Or you can use the formulas and charts that follow to do the calculations yourself.

1Convert your child’s weight from pounds to kilograms.

Weight (in pounds) ÷ 2.2 = weight (in kilograms).

For example, 75 pounds ÷ 2.2 kilograms = 34 kilograms.

2Convert your child’s height from inches to meters.

Height (in inches) ÷3 9.37 = height (in meters). For example, 48 inches ÷ 39.37 meters = 1.22 meters.

3Calculate your daughter’s Body Mass Index using the chart below.


4Calculate your son’s Body Mass Index using the chart below.

As a general rule, a child whose BMI is over the 85th percentile for age and sex, needs to be evaluated for hypertension and high blood fats, because his weight is dangerously unhealthy. If the child’s BMI is over the 95th percentile for age and sex, a thorough medical assessment is needed.

Many of the health concerns that are equated with midlife are showing up in overweight children. So, it’s important to become your child’s advocate to ensure that her doctor is identifying and treating any health problems early on. For more information, check out and search for BMI.