How to Figure Out a Child's Body Mass Index

The body mass index scale or BMI as it is commonly called, is used to determine a healthy weight for an individual. Although it is typically associated with adults, it can also be used for children. While the BMI scale is a guideline for healthy weights, it does take into account frame size when determining a healthy weight. There are four main categories in a BMI measurement: underweight, normal, overweight and obese. Determining where your child fits into these categories can help parents with their child's nutrition plans and overall health program.

Instructions

• 1

  Determine your child's current height. The overall height of the child is necessary to calculate their body mass index. If you have not measured them recently, get a new measurement to make sure of their exact height. Convert this height into inches, i.e., a child who is 4 feet, 6 inches would be 54 inches tall. Make a note of this number.

• 2

  Weigh your child. Using a regular body weight scale, weigh your child. Have them hold still and make certain that they are not leaning. Their weight should be centered in the middle of the scale. Make a note of this number.

• 3

  Use the following formula to determine their body mass index

  BMI = Weight (lb) / (Height (in) x Height (in)) x 703

• 4

  Use an online calculator. If you prefer, you can also calculate your child's body mass index using a calculator that performs the above equation for you and returns the value of your child's BMI. This is a simpler method to reach the same conclusion. Please see the reference section for a free online calculator.

• 5

  Determine where your child's weight is on the BMI tables. Please see the reference section in this article for a link to the current Body Mass Index tables for Children. Take the number you got from either your own calculations or an online calculator and their age to find the spot on the graph where your child fits. This will help you determine what category they fall in and if you need to make any alterations to their current diet.