How to Calculate How Tall a Child Will Grow

Not only is it fun to predict how tall your child will grow, it can also help you and your doctor track your child's development. Genetics play a big role in predicting a child's adult height, but the nutrition and exercises you expose your child to also factor into his growth. There are a variety of ways outlined below to calculate how tall your child may grow to be. According to Linda Shaw, M.D. it is best to start calculating once your child is a toddler because a child's height during the first year of life is a result of intrauterine conditions.

Things You'll Need

• Height calculator
• Growth charts

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Instructions

• 1

  Combine the total inches in the mother's height and father's height.

• 2

  Add five inches for a boy and subtract five inches for a girl.

• 3

  Divide by two for the predicted height. This method, shared by Jay L. Hoecker, M.D., of the Mayo Clinic, finds that most children reach an adult height that is within four inches of the prediction.

• 4

  Analyze your child's placement on a growth chart after she has reached 2 years of age. A child in the 10th percentile with short parents, will likely stay near that placement. Follow the curve of the chart to predict future growth. The U.S. Centers for Disease Control and Prevention (CDC) provides growth charts for boys and girls from birth to age 20 (see Resources at the end of this article).

• 5

  Alternatively, use an online calculator like the one in the Resources section of this article. This calculator also takes into account a child's height and weight and is most effective to use with children 4 years or older. It was developed by Harry Khamis, M.D. and Alex Roche, M.D., of Wright State University and has a margin of error of two inches.

• 6

  Have the doctor perform a "bone-age" X-ray. The doctor can give a fairly accurate prediction of your child's future height after examining the hand and wrist. However, there are negative side effects to this method, and it should be considered only if there are concerns about your child's development.