1. What is BMI for Children?

Body Mass Index (BMI) for children is a screening tool that assesses whether a child is underweight, healthy weight, overweight, or obese. Unlike adults, children's BMI is interpreted relative to age and sex-specific percentiles.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

• \( weight \) — Measured in kilograms (kg)
• \( height \) — Measured in meters (m)

Explanation: The result is compared to CDC growth charts to determine the child's BMI percentile for their age and gender.

3. Importance of BMI Calculation

Details: Regular BMI screening helps identify potential weight problems in children. Early identification allows for lifestyle interventions to promote healthy growth.

4. Using the Calculator

Tips: For accurate results, measure height without shoes and weight with minimal clothing. Use precise measurements in metric units (kg and m).

5. Frequently Asked Questions (FAQ)

Q1: What do the percentiles mean?
A: Below 5th percentile = underweight; 5th-85th = healthy weight; 85th-95th = overweight; Above 95th = obese.

Q2: Why use percentiles for children?
A: Children's body composition changes with age, so BMI must be interpreted relative to peers of same age and sex.

Q3: How often should children's BMI be checked?
A: The AAP recommends annual BMI screening starting at age 2.

Q4: Are there limitations to BMI for children?
A: BMI doesn't distinguish between fat and muscle mass. Athletic children may have high BMI without excess fat.

Q5: Where can I find CDC growth charts?
A: CDC growth charts are available for download at cdc.gov/growthcharts.