1. What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight to assess weight status. For children, BMI is particularly important for identifying potential weight problems, though age is typically needed for percentile classification.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

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

Note: For a complete pediatric assessment, age and sex-specific percentile charts should be consulted.

3. Importance of BMI Calculation

Details: BMI helps identify children who may be underweight, overweight, or obese. Early identification allows for timely intervention and healthy lifestyle guidance.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For accuracy, measure height without shoes and weight with minimal clothing.

5. Frequently Asked Questions (FAQ)

Q1: Why is age typically needed for pediatric BMI?
A: Children's body composition changes with age, so BMI percentiles (rather than absolute values) are used for classification.

Q2: What are the limitations of BMI for children?
A: BMI doesn't distinguish between muscle and fat, and doesn't account for growth patterns or puberty timing.

Q3: How often should children's BMI be checked?
A: The NHS recommends annual BMI checks as part of the National Child Measurement Programme for children aged 4-5 and 10-11.

Q4: What's a healthy BMI range for children?
A: Without age-specific percentiles, general adult ranges can be used as a rough guide: underweight (<18.5), normal (18.5-24.9), overweight (25-29.9), obese (≥30).

Q5: Where can I get age-specific BMI percentiles?
A: The UK NHS Growth Charts or the Royal College of Paediatrics and Child Health provide detailed percentile charts.