This BMI Calculator for Children is a BMI percentile calculator for children and teenagers that provides BMI and the corresponding BMI-for-age percentile. The calculations are based on the CDC growth charts for children and teens between the ages of 2 and 20 years. To perform calculations choose appropriate measurement units and specify the height, weight and age either using the sliders or inserting the data in the calculator fields, then specify the gender.
BMI for children
The Body Mass Index (BMI) is known to be used as a screening tool to identify possible weight problems in children. The BMI is defined as the body mass of a person divided by the square of the person’s height, and is commonly expressed in units of kg/m2, resulting from mass in kilograms and height in meters.
Unlike adults for whom a BMI of 18.5 to 25 is considered normal and corresponds to healthy weight, children require a different approach to weight evaluation given that their bodies change so rapidly. BMI for children is calculated in the same way as for adults, but then it compared to typical values for other children of the same age. Instead of comparison against fixed thresholds for underweight and overweight, the BMI is compared against the percentiles for children of the same sex and age.
So, if a child is, say, in the 65th percentile, that would mean that he or she is higher in terms of BMI than 65 percent of all children of that sex and age group. In terms of weight, higher percentile values correspond to higher weight categories, while lower percentile values correspond to lower weight categories.
The BMI-for-age weight categories are based on recommendations from an expert committee organized by the American Medical Association (AMA), the Centers for Disease Control and Prevention (CDC), and the Human Resources Services Administration (HRSA), and defined as follows:
• Underweight – BMI below the 5th percentile.
• Normal weight – BMI between 5th and 85th percentile.
• Overweight – BMI between 85th and 95th percentiles.
• Obese – BMI above 95th percentile.
Below is presented a typical BMI-for-age graph. The clinical growth charts for boys and girls of ages 2 to 20 years can be found on the CDC website.
After the BMI value is calculated, our BMI calculator for children and teens expresses it as a percentile which is obtained from the data table of the CDC BMI-for-age charts.
Like any other BMI for kids calculator our online calculator is not a diagnostic tool and can be used only to screen for potential weight and health-related issues. So, in case of abnormal child’s BMI value for their age and sex a health care provider would need to perform further assessments, including skin-fold thickness measurements, evaluations of diet, physical activity, family history, and other appropriate health screenings.
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Check out our other health calculators such as BMI Calculator or Child Height Predictor.
Disclaimer. Please remember that this calculator is only one of many ways to assess your weight. In case of any concerns about your weight, please consult your physician to address your specific situation.