BMI Calculator for Children and Teens

Body mass index (BMI) is one way to estimate a person's body fat that takes into consideration the person's height. BMI is calculated using a person's weight and height. In children and teens, BMI is used to find out if a child or teen is underweight, of a healthy weight, overweight, or obese. A child's body fat changes with age. Also, girls and boys differ in their amount of body fat as they mature. This is why BMI for children, also known as BMI-for-age, includes gender and age.

This calculator gives an approximate BMI for children from ages 5 to 18. It will tell you if a child is underweight, at an ideal weight, at risk of being overweight, or is now overweight.

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This calculator is not intended to replace the evaluation of a health care professional.

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1. CF affects which body system?
2. How many Americans are carriers of the abnormal CF gene?
3. Which symptom in an infant or young child might mean CF?
4. What happens to the mucus glands in a child with CF?
5. How is the digestive system affected by extra mucus in CF?
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