Children and teens are still growing; CDC recommends age-and-sex-specific percentiles.
Child and Teen BMI Calculator
Calculate BMI-for-age using CDC percentiles for people ages 2–19.
BMI percentile for growth.
Unlike adults, children and teens use BMI compared with people of the same reference age and sex. The tool calculates BMI, approximate z-score, percentile and CDC category.
Enter exact age, reference sex, height and weight.
- Use age in years and months, from 2 through 19.
- Measure height and weight consistently, without shoes and with a reliable scale.
- Read the percentile as educational screening, not a standalone diagnosis.
Why percentile matters
Children grow at different rates. Percentile compares BMI with the CDC reference population of the same age and sex, so it is more appropriate than fixed adult ranges.
Race is not part of the CDC BMI percentile calculation; age, sex, weight and height are the required inputs.
- Below 5th percentile: underweight.
- 5th to below 85th: healthy weight.
- 85th to below 95th: overweight.
- 95th or higher: obesity; 120% of P95 signals severe obesity.