BMI Calculator

BMI Chart
Adults
 
Ages 2-19
(Percentiles)
Under Weight <18.5 <5th
Normal Weight 18.5−<25 5th−<85th
Overweight 25−<30 85th−<95th
Obese (Class I) 30−<35 >=95th
Obese (Class II) 35−< 40 >=120%−<140%
of the 95th
Obese (Class III+) >=40 >=140%
of the 95th

Health professionals use a BMI Calculator to determine if you are at a healthy weight for your age and height. You can enter some basic information about yourself into Pennington Biomedical’s BMI Calculator to learn the following:

BMI

BMI (Body Mass Index) is an estimate of body fat and is calculated for both children and adults. A high BMI might mean you are at a higher risk for diseases associated with obesity.

BMI Percentile

The BMI Percentile is calculated for children and young adults aged 2 to 19.  Health professionals can use the percentile score to categorize a child’s BMI to identify where the child falls in relation to other children of the same age and sex.

Z-Score

BMI Z-Scores are also calculated for children and young adults aged 2 to 19. This number indicates how much higher or lower your BMI is on a standard growth chart. BMI Z-Scores help health professionals to monitor weight changes in children and adolescents especially if they are in the underweight or overweight percentiles.

How to Measure a Child’s Height

Measuring a child’s height and weight at each visit allows the provider to calculate the child’s Body Mass Index (BMI) and BMI percentile. These instructions can be used to train new clinic staff who will be taking measurements for pediatric patients. It can also be provided to patient caregivers for home use if needed.