1. What is BMI?

BMI (Body Mass Index) 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:

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

For children: The BMI value is plotted on standard growth charts to determine the percentile ranking based on age and sex.

3. Importance of BMI Calculation

Details: BMI-for-age is the recommended measure for screening overweight and obesity in children and teens. It helps identify potential weight problems that may lead to health issues.

4. Using the Calculator

Tips: Enter weight in kg, height in meters, age in years (2-18), and select gender. For accurate results, measurements should be taken with minimal clothing and no shoes.

5. Frequently Asked Questions (FAQ)

Q1: What is a healthy BMI for children?
A: Healthy weight is between the 5th and 85th percentiles. Below 5th is underweight, 85th-95th is overweight, and above 95th is obese.

Q2: Why is BMI different for children than adults?
A: Children's body composition varies with age and sex, so BMI must be interpreted relative to other children of the same age and sex.

Q3: How often should children's BMI be checked?
A: Yearly checks are recommended for all children aged 2 years and older.

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: Where can I find growth charts?
A: The CDC provides standard growth charts that show BMI percentiles by age and sex.