1. What is BMI?

Body Mass Index (BMI) is a measure of body fat based on height and weight that applies to adults and children. For children and teens, BMI is age- and sex-specific and is often referred to as BMI-for-age.

2. How Does the Calculator Work?

The calculator uses the BMI formula:

Where:

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

For children: The result is compared against age- and sex-specific percentiles from growth charts.

3. Importance of BMI Calculation

Details: BMI screening helps identify potential weight problems in children, but it's not a diagnostic tool. A healthcare professional performs further assessments.

4. Using the Calculator

Tips: Enter weight in kg, height in meters, age in years (2-18), and select gender. For accurate results, measure height and weight without shoes and heavy clothing.

5. Frequently Asked Questions (FAQ)

Q1: Why is BMI different for children?
A: Children's body composition varies by age and sex, so BMI must be interpreted relative to other children of the same age and sex.

Q2: What are healthy BMI ranges for children?
A: Healthy ranges vary by age and sex. Generally:

• Underweight: <5th percentile
• Healthy weight: 5th to <85th percentile
• Overweight: 85th to <95th percentile
• Obese: ≥95th percentile

Q3: When should I be concerned about my child's BMI?
A: Consult a doctor if your child's BMI is below the 5th percentile or at/above the 85th percentile.

Q4: Are there limitations to BMI?
A: BMI doesn't distinguish between muscle and fat, and may not accurately reflect body fatness in very muscular children.

Q5: How often should children's BMI be checked?
A: Yearly checks are recommended as part of routine health supervision.