When you have a child, it is common to worry about many things, and growth expectancy is near the top of the list for most parents. It doesn’t matter if you have a boy or a girl, you’ll wonder how tall they will grow. The factors that contribute to a child’s growth will vary, with growth being largely determined by genetics. Nutrition and overall wellness will also play a role, but not to the extent that genetics plays.
Then there is puberty, which for a little while will throw you off. When the child is twelve, a common age for puberty and growth, you should pay attention.
The average height of a twelve-year-old boy or girl will be 58 or 59 inches, or almost five feet tall. The average height can range as high as 64 inches, but a twelve-year-old can also be much shorter than this.
The average height for pre-teens at twelve years old will be in the 58 to 59 inches range. However, children that aren’t in this range yet, or have surpassed it, are on the ends of a normal bell curve. There are a number of reasons for this, and you can learn more about those reasons, and the average height of a 12-year-old here.
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It is very difficult to predict how tall a child will be at any age, although every parent and doctor will try to by using averages and clinical growth charts. The heights of the parents are the best predictors of a child’s height, though no formula is going to be exact. Still, many doctors and laypeople alike use a popular formula to predict the height expectancy of a child.
This is done by adding the height of the two parents in inches or centimeters, depending on the system you use. Add five inches or 13 centimeters for boys, and subtract five inches or thirteen centimeters for girls. Divide this number by two and you should have a general predictor of height for any child.
Say, for example, you have two parents who are both 5 feet and 9 inches tall. That is 69 inches tall times two, or 138 inches. That is 175 centimeters each or 350 centimeters in total. Dividing by two, you get 175 centimeters. Their daughter’s height expectancy would be 64 inches or 162 centimeters, and their son would be 74 inches or 188 centimeters, or, 6 feet and two inches tall.
It doesn’t make much sense with that formula, but it is one that is used frequently by centers such as the Mayo Clinic.
Children are said to reach their maximum height by the age of 18, although some still keep growing after that. Most growth charts indicate that a teen will grow four to six inches between 12 and 18 years. That would put the hypothetical child at the height of 5 feet 8 inches to 5 feet 10 inches at the age of 12, which could happen.
It is impossible to predict height, but we can give averages. Formulas such as this, combined with growth charts, help to provide average heights at certain ages.
Typical heights and average heights are different things. A typical height is what you would expect, and we look to growth charts for this. An average height is the average of all of the heights of a specified group. If we took, for example, every twelve-year-old in one school classroom, we could find an average height. It might be a different average from the average height of another school classroom, even in the same building. Yet we might find an answer that was a typical height of twelve-year-olds.
At 12, standardized growth charts distributed by the CDC indicate that girls are going to be approximately 55 to 64 inches tall, which is 4’7” to 5’4” tall. The average weight for this age group ranges from 68 to 136 pounds. At 12, the range for boys is very similar, using the same growth charts. Boys are typically in the 54 to 63.5-inch range in height, which is 4’6” tall to 5’3.5” tall. Weight for boys ranges from 66 to 130 pounds.
It is a general rule of thumb that, on average, as height increases so does weight. When you are wondering how tall a child will be at the age of 12, weight is a good indicator to help make that prediction.
One of the biggest issues with trying to find an average height for twelve-year-olds is the issue of puberty. Puberty happens at different rates for every person, and this will throw off the averages. Boys and girls also reach puberty at different rates, with girls, on average, reaching puberty first. Puberty is where growth spurts occur, with the greatest growth rates happening between the ages of 12 and 15 for both boys and girls. It is not unusual for girls to be taller than boys of the same age, and this is an indicator that they are in puberty or close to it.
Prior to puberty, children of both genders will grow at a rate of approximately two to four inches annually. Boys are going to have their biggest growth spurt between 10 and 16 years of age, and girls will have theirs two years before them. A child can grow as much as 11 inches in that time span.
Again, look to family history to determine what the average height projection will be for a twelve-year-old in any family. When did the siblings or parents begin puberty and reach their growth spurts?
When a child reaches puberty will not determine the extent of their height projections at adulthood. If a child reaches puberty at the age of 11 for example, they won’t necessarily become taller because they have their growth spurt earlier. They might have a small growth spurt and grow until they reach 18. Or, they may stop growing a little earlier. At the same time, a child that reaches puberty later is not necessarily going to be shorter as an adult either. They may have a wild growth spurt in a short span of time and wind up a taller adult than the twelve-year-old who grew three shoe sizes in the same year.
While girls may start puberty earlier, their growth spurts are a little different than boys. They will typically have a smaller growth spurt around the age of 12 and be taller than their male counterparts at school. However, this typically does not last longer than a year. Girls will grow one or two inches every year after they begin menstruating.
Wellness plays a significant role in the average height of a twelve-year-old, and there are many factors here as well. Nutrition is important, as nutrition helps bones, muscles, and tissues to lengthen and expand. Sleep plays a role here as well.
For the first several years of their life, children sleep a lot. This is because they are growing. Growth requires cell division, which requires sleep and rest. Without these things, growth can be inhibited.
Pre-teens and teens will also get very tired over long school days. A day out shopping as well may be a blast for everyone, but they might fall asleep in front of the movie that night at 8 PM. They are probably growing, especially if this kind of day happens during puberty.
Other factors of wellness play a role as well. Nicotine and caffeine can affect growth as well, one reason being that these substances interfere with sleep and thus, cell division and other important bodily functions that contribute to human height potential.
The average height of a twelve-year-old then will depend on a lot of factors:
For boys, the average height in the fiftieth percentile is 58.7 inches or 4’10” tall. By the age of 20, a boy of this height will become 5’9” if the growth rate remains consistent.
For girls, the average height in the fiftieth percentile is slightly higher at 59 inches, which is 4’11” tall. Some twelve-year-olds will be five feet tall and still be in the fiftieth percentile.
It is important to remember that when you are projecting height and growth rates that it is all relative. Genetics plays a significant role here, perhaps the most significant one. Wellness plays a significant role as well, and in many nations, is the most determining factor for the height potential of a twelve-year-old.
Taking every chart and standardized measure known into consideration, the average height of a twelve-year-old is going to be around 4’10 inches tall, which is 58 inches or 147 centimeters tall.