Body Mass Index (BMI) for children and teens is different from adult BMI. It’s often referred to as “BMI-for-age” because it considers a child’s age and gender, as body composition changes with growth.

How to Measure Accurately:

• Age: Use the child’s exact age in years and months.
• Height: Measure height without shoes, standing straight. For young children, measure length while lying down if they cannot stand.
• Weight: Measure weight with minimal clothing and no shoes, preferably on the same scale each time.

BMI Calculation:

• BMI = Weight (kg) / [Height (m)]²
• Or: BMI = [Weight (lbs) / (Height (in))²] x 703

Interpretation:

For children and teens (ages 2-19), BMI is plotted on gender-specific BMI-for-age percentile growth charts (e.g., from the CDC or WHO). This calculator provides the BMI value. A healthcare provider uses this value along with percentile charts to assess weight status:

• Underweight: Less than the 5th percentile.
• Healthy weight: 5th percentile to less than the 85th percentile.
• Overweight: 85th to less than the 95th percentile.
• Obesity: Equal to or greater than the 95th percentile.

Critical Disclaimer: This calculator provides a BMI value for informational purposes ONLY. It does NOT provide percentile rankings or a diagnosis. BMI is a screening tool, not a diagnostic tool. ALWAYS consult a pediatrician or healthcare provider for a proper assessment of your child’s growth and health. They will consider BMI in the context of overall health, growth patterns, family history, and other factors.