This pediatric BMI calculator gives the BMI percentile of a child or teen from 2 to 19 years old. Type the age, the sex, the height and the weight.
For information only. BMI is a screening tool. It does not diagnose a health problem. Talk to a health care provider about your weight and your health.
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What a percentile means
A percentile compares a child with other children of the same age and sex. At the 62nd percentile, the BMI is the same as or higher than the BMI of 62 out of 100 children.
Why age and sex matter
The amount of body fat changes as a child grows. It is also different for boys and for girls. So the CDC does not use the adult categories for children.
A BMI by age compares the child with children of the same age and sex.
The CDC categories for children
Underweight: below the 5th percentile. Healthy weight: from the 5th percentile to below the 85th.
Overweight: from the 85th percentile to below the 95th. Obesity: the 95th percentile or above.
Severe obesity: a BMI of 120% of the 95th percentile or more, or a BMI of 35 or more.
Children under 2
For children under 2, the CDC uses the WHO charts. Ask a health care provider.
How BMI is calculated
BMI equals the weight in kg divided by the height in meters, squared.
In US units, BMI equals 703 times the weight in lb, divided by the height in inches, squared.
Example: a person weighs 70 kg and is 175 cm tall. The height is 1.75 m. BMI equals 70 divided by 1.75 squared. That is 22.9.
A percentile compares a child with other children of the same age and sex. At the 62nd percentile, the BMI is the same as or higher than the BMI of 62 out of 100 children.
Why do age and sex matter for the BMI of a child?
The amount of body fat changes as a child grows. It is also different for boys and for girls. So the CDC compares a child with children of the same age and sex.
What are the BMI categories for children and teens?
The CDC uses percentiles. Below the 5th percentile is underweight. From the 5th to below the 85th is a healthy weight. From the 85th to below the 95th is overweight. The 95th or above is obesity.
What is severe obesity in a child?
The CDC calls it severe obesity when the BMI is 120% of the 95th percentile or more, or when the BMI is 35 or more.
Can I use the calculator for a child under 2?
No. For children under 2, the CDC uses the WHO charts. Ask a health care provider.
Does the calculator send my height and weight to a server?
No. The calculator works in your browser and sends nothing. Your height, weight and age stay on your device. The page saves nothing. Read more about privacy.