1. What is BMI for Children?

BMI (Body Mass Index) for children and teenagers is age- and sex-specific and is often referred to as BMI-for-age. Unlike adults, children's body composition varies as they age and differs between boys and girls, so BMI must be interpreted relative to growth charts.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

• \( weight \) — Body weight in kilograms
• \( height \) — Height in meters

Important: For children and teens, the raw BMI number must be plotted on CDC growth charts to determine the corresponding BMI-for-age percentile.

3. Importance of BMI Calculation

Details: BMI-for-age is the most common screening tool for identifying potential weight problems in children. It helps identify underweight, healthy weight, overweight, and obesity in children and teens.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, age in years (2-19), and select gender. For accurate results, measurements should be taken with minimal clothing and no shoes.

5. Frequently Asked Questions (FAQ)

Q1: Why is BMI interpreted differently for children?
A: Children's body composition changes as they grow, and differs between boys and girls, so BMI must be compared against age- and sex-specific standards.

Q2: What are the BMI categories for children?
A: Underweight (<5th percentile), Healthy weight (5th-85th percentile), Overweight (85th-95th percentile), Obese (≥95th percentile).

Q3: When should BMI be measured in children?
A: The American Academy of Pediatrics recommends BMI screening annually from age 2.

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

Q5: What should I do if my child's BMI is concerning?
A: Consult with a pediatrician who can perform additional assessments and provide guidance.