Child BMI Calculator
Calculate a child's BMI with age, sex, height and weight, then review an approximate BMI-for-age percentile band and screening caveats.
Kilograms
Centimeters
Note: BMI-for-age is screening only; adult BMI cutoffs do not apply to children.
This calculator is intended for children and teens ages 2 through 19 and shows an approximate percentile band, not an exact CDC percentile.
- Underweight: Less than 5th percentile
- Healthy weight: 5th to less than 85th percentile
- Overweight: 85th to less than 95th percentile
- Obesity: 95th percentile or higher
Child BMI-for-age screening
Child and teen BMI is interpreted differently from adult BMI. The English search intent expects age, sex, height, weight, a BMI value, and BMI-for-age context for ages 2 through 19.
Body mass index formula used before age-and-sex interpretation.
How to read the category
| Approximate percentile band | Screening category | Meaning |
|---|---|---|
| Less than 5th percentile | Underweight | Below the approximate reference band for the selected age and sex. |
| 5th to less than 85th percentile | Healthy weight | Approximate middle BMI-for-age band. |
| 85th to less than 95th percentile | Overweight | Screening flag that should be interpreted with growth history. |
| 95th percentile or higher | Obesity | Screening flag, not a diagnosis by itself. |
Adult BMI cutoffs do not apply to children. Age in months, puberty, family history, growth velocity, medical conditions, activity and nutrition can all change interpretation.
Frequently Asked Questions
Sources and References
- Child and Teen BMI CalculatorCDC
- Child and Teen BMI CategoriesCDC
- BMI-for-age Growth ChartsCDC
- Clinical Practice Guideline for the Evaluation and Treatment of Children and Adolescents With ObesityAmerican Academy of Pediatrics
Calculations are based on the listed reference sources. Links open in a new tab.
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