When Do Boys Stop Growing?

Teenagers grow at all different rates. Here's how pediatricians answer the age-old question: When do boys stop growing?

Your 15-year-old may not have had a growth spurt in a while, but does that mean the days of going through endless pairs of shoes and too-tight T-shirts are behind you? Not necessarily.

Boys tend to develop about two years later than girls, and it’s possible for them to continue growing well into their teen years. When they’re done growing for good, however, depends on several factors.

The Average Age at Which Boys Stop Growing…

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It’s 16. Boys usually experience a rapid growth spurt between the ages of 12 and 15. This is all thanks to that pesky thing called puberty. By the time boys turn 16, most of them have stopped growing in height and have already acquired the deeper voice they’ll have for the rest of their lives.

The time at which they start puberty affects when they’ll finish it, so expect late bloomers to stop growing a year or two later than early birds. While most boys don’t get much taller after 15 or 16, muscular development is a different story. Boys continue packing on more muscle until their late teens or early 20s, so clothing size will continue to change as well.

Genes Aren’t Everything, but They Count for a Lot

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A boy’s adult height is determined by several factors, but nutrition and genetics are the two big ones. Based on studies of twins, researchers believe that genes influence height and body type by about 60-80 percent. In other words, your genes are like a blueprint.

They provide the instructions to tell your body how large to grow and when to stop. That’s where nutrition comes in. Your body does its best to follow the instructions its given, and eating healthy food helps it to max out its height potential.

That’s why identical twins are usually about the same height, with slight variation depending on lifestyle factors. Countries with improved nutrition tend to see an increase in average height, but eating your veggies won’t overwrite your genes.

In other words, boys who take after their 4-foot-11 grandma probably won’t be joining the NBA anytime soon, no matter what they eat. Sorry, kid.

How Accurate Are Growth Charts, Really?

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The truth is, despite all our advancements in science and medicine, there’s no surefire way to predict exactly how tall a boy will grow. Growth charts are based on formulas, but they’re only an estimation. Adult height can vary up to about four inches in either direction from the number suggested by growth charts.

As long as your teen’s doctor isn’t concerned about their growth, you shouldn’t be either. Genes play the biggest role, so as long as your child is developing at a healthy rate and eating well, just keep doing what you’re doing and let nature take its course.

As much as they’d love to know if they’ll hit six feet, it’s best to think of their adult height like a fun surprise and not make too big of a deal about it.

How Can You Tell When Boys Have Reached Their Adult Height?

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Height officially stops increasing when a child’s growth plates close. The growth plates are made of a special type of cartilage located at the end of your long bones. When the growth plates are “open,” growth continues. At the end of puberty, shifting hormones cause the growth plates to harden, putting an end to vertical growth for good.

This typically occurs between the ages of 14 and 19 in young men. It’s technically possible for a boy to continue growing after 18, but it’s uncommon and likely won’t amount to more than an extra inch. If a boy in his late teens has stayed the same height for several months, the odds are good that he’s done growing.

With that in mind, having open conversations with your teen about health and body image is important. While more focus is often placed on the body image and self-esteem of teen girls, boys are also susceptible to worrying about how they look compared to men in the media.

Teaching teens how to take care of both their physical and mental health can improve their self-confidence and help ward off worries about how they size up to their peers.