Child BMI Calculator

Age — BMI percentiles are only meaningful for ages 2–20 using the CDC growth charts.
Height & weight — measured values; enter metric units for the most accurate estimate.

Frequently Asked Questions

What does BMI percentile mean?

It tells you how your child compares with other children of the same age and sex. The 50th percentile is the median.

How is child BMI categorized?

Underweight is below the 5th percentile, healthy weight is 5th–85th, overweight is 85th–95th, and obesity is at or above the 95th.

Why can't I use adult BMI categories for children?

Children grow and their body composition changes, so BMI is judged against age- and sex-specific percentiles instead of fixed cutoffs.

Is this a diagnosis?

No. Percentiles are a screening tool. Always discuss results with your child's pediatrician.

A 10-year-old boy, 140 cm tall and 35 kg:

How to Use This Calculator