According to Dr. Robert H. Shmerling for InteliHealth, there are many factors involved in determining the height a child will ultimately reach. Some of the major determinants of a person's height are gender, general health, bone growth and genetics.
Dr. Shmerling, a physician at Beth Israel Deaconess Medical Center, notes that there are some simple formulas that people use to try and predict a person's eventual height. Most formulas lead to an approximation of what a person's height will be, but the formulas are not guarantees. One of the more common formulas is based on the height of a person's mother and father. For men, the eventual height is the height of the mother plus the height of the father plus 5 and then divided by 2. For women, the height is the height of the mother plus the height of the father minus 5, then divided by 2. According to Dr. Shmerling, this formula is usually accurate within 2 or 3 inches for most people.