BMI calculator for kids
A child's or teenager's BMI-for-age percentile from the CDC's growth charts, with the 2022 extended percentiles. Free, with no account or uploads.
A child's BMI percentile for age
Type the child's age in years and months, sex, height and weight. Children are judged by percentile, not the adult bands.
The formulas were measured separately for women and men.
Children are read against their age to the month.
BMI 17.1 for a girl of 10 years
53rd percentile
Healthy weight for age, by the CDC's charts (healthy is the 5th to below the 85th). At this age the 50th percentile is a BMI of 16.9 and the 85th is 20.0.
A little help along the way
Follow these steps. Every option is explained underneath. Everything runs in your browser; nothing is sent anywhere or kept.
- Say what you want to knowBMI, calories a day, or body fat.
- Choose your measuresCentimetres and kilograms, or feet, inches and pounds.
- Type your age, height and weightAnd your sex for calories, body fat and a child's BMI; for body fat, your waist, neck and hips.
- Read the answerIn words first, with the formula it came from.
Questions people ask
- Why a percentile and not the adult bands?
- Children's BMI changes as they grow and differs by sex, so the CDC compares it with children of the same age and sex; the adult bands do not apply under 20.
- What are the extended percentiles?
- The CDC's 2022 charts go above the 97th percentile for children with obesity, so a very high BMI still gets a meaningful number; the page uses them above the 95th.
- What ages does it cover?
- 2 to 19 years, as the CDC's charts do. Babies are measured by weight-for-length instead, which the page does not chart.
This page is the BMI and calorie calculator, opened for this one job; every other tool it has is one press away. Each of its settings is explained on the BMI and calorie calculator's own page.
Read the step-by-step guide