When Do Boys Stop Growing?

Most boys stop growing taller between 16 and 18, once puberty is over and the growth plates in their bones have closed. On CDC growth charts, the median boy has only about 1.3 inches (3.4 cm) left at 16 and roughly a quarter inch (0.7 cm) at 18. Late bloomers run on a later schedule, and a few gain a little after 18, usually an inch or less.

What age do boys stop growing?

There is no single birthday when growth switches off. Nemours KidsHealth says most boys have stopped growing by about 16, while Cleveland Clinic puts the usual finish line between 16 and 18. Both are right for different boys, because the end of growth is tied to puberty, not to age.

Puberty normally starts between 9 and 14 in boys. Its hormones first speed up growth (the growth spurt) and then gradually close the growth plates, the softer areas near the ends of long bones where new bone is made. A boy who starts puberty at 10 will usually finish growing years before a classmate who starts at 14.

Height is not the only thing still changing, though. Muscles keep developing after height stops, which is why many guys keep filling out in their late teens.

Boys' height by age (CDC medians)

These are medians for US boys, so half are taller and half are shorter at each age. Timing matters as much as height: a boy can be two years ahead of or behind this schedule and still be completely normal. To see how your own numbers compare, try the height calculator.

When do boys hit their growth spurt?

Boys grow fastest between about 12 and 15, roughly two years later than girls. In a classic review of US data, the average boy's peak came at about 13.5 years, when he grew around 3.7 inches (9.5 cm) in a single year. Puberty as a whole adds about 12 inches (30 cm) to a boy's height.

The median curve in the table looks smoother than real life because it averages early and late developers together. Your own spurt is likely to be sharper and shorter than the chart suggests.

In boys the spurt peaks in the later stages of puberty, after the testicles have grown and pubic hair has appeared. The voice usually drops just after the peak. Our growth spurt guide covers the timing and signs in detail.

Signs you're almost done growing

No single sign proves you are finished, but several together are a good clue:

• Your growth has nearly stopped. In medical studies, growing less than about 0.4 inch (1 cm) over a full year is often treated as reaching final height.
• Your voice has fully deepened. It changes just after the growth peak, so a settled adult voice means your fastest growth is behind you.
• You shave regularly. Facial and underarm hair usually arrive about two years after pubic hair, and chest hair comes later still.
• Your body looks adult. Adult-size genitals arrive anywhere from 13 to 18, along with adult body hair and broader shoulders.
• Your shoe size has stopped changing. This is a weak sign on its own, because feet often do their fast growing early in puberty.

The only way to know for sure is a bone age X-ray read by a doctor. Our guide on how to tell if your growth plates are closed explains what that test shows.

When do men stop growing?

For nearly all men, height growth is finished by 18 to 20. Cleveland Clinic notes that growth past 18 is rare and usually adds an inch or less when it does happen. Growing at 19 or 20 is not automatically a problem, but it is worth mentioning to a doctor, and there is no evidence of height growth past 25.

The CDC numbers tell the same story: the median boy gains only about 0.3 inch (0.7 cm) between 18 and 20. US men aged 20 and older average 68.9 inches, about 5'9" (175 cm). If you are already past 18, read can you grow taller after 18? for what is and isn't possible.

Will my son keep growing after 16?

It depends on where he is in puberty, not on the number 16. If his big growth year was two or more years ago, his voice is deep and he shaves, he probably has little height left. The median 16-year-old has reached about 98% of his adult height.

If he is still small for his age, has little facial or body hair and his voice has not changed, he may be a late bloomer with real growth ahead. This pattern, called constitutional delay of growth and puberty, affects over 2% of teens, mostly boys, and runs in families in 50 to 75% of cases. Ask whether either parent was a late developer. Most late bloomers end up within the normal adult range, though some studies find they finish slightly below what their parents' heights predict. Read more in our late bloomer guide.

How much taller will I get?

You can get a reasonable estimate at home:

1. Track your growth. Measure yourself barefoot, at the same time of day, every three months. Your growth rate over the last year is the best clue you have.
2. Use your growth curve. Most teens stay near the same percentile on the CDC chart, adjusted for whether they are early or late in puberty.
3. Use your parents' heights. Add 5 inches to your mom's height, add your dad's height, and divide by two. Most boys end up within about 4 inches of that number. The mid-parental height calculator does the math for you.
4. Ask about a bone age X-ray. A single X-ray of the left hand and wrist shows how mature your bones are and roughly how much growing time is left.

The Am I done growing? quiz combines your age, recent growth and puberty signs into a quick estimate.

What helps you reach your full height

Genes set the range for your adult height. What you control is whether you reach the top of that range while your growth plates are still open:

• Sleep 8 to 10 hours a night, the amount sleep experts recommend for ages 13 to 18.
• Eat enough. Growth needs energy, protein, calcium and vitamin D. Skipping meals or training very hard without eating enough can delay puberty.
• Stay active and get regular checkups so health problems that slow growth are caught early.

Nothing (stretching, hanging, pills or special foods) can push you past your genetic range or add height after the growth plates close. Our guide on how to grow taller separates what works from what doesn't.

When to see a doctor

Talk to a doctor if any of these apply:

• No signs of puberty, such as testicles getting bigger, by age 14.
• Puberty started but seems stuck or is moving very slowly.
• Your growth was normal and then slowed down a lot, or you are dropping to lower percentile lines over time.
• Signs of puberty began before age 9.
• You are on track to end up far shorter than your parents' heights suggest.
• You are still growing noticeably at 19 or 20.
• Worry about your height or development is affecting your mood, school or friendships.

A doctor can review your growth chart, order a bone age X-ray and blood tests, and refer you to a pediatric endocrinologist if needed. Any hormone or growth treatment is decided by that specialist after testing.

The short version

Most boys finish growing between 16 and 18, with late bloomers sometimes adding a little more until about 20. Your puberty stage and your growth over the past year say far more than your age does. If you are still growing, sleep, food and activity help you reach your full potential, and a doctor can answer the question for certain if you are worried.