Most girls reach their final adult height between ages 14 and 16, while most boys stop growing taller between 16 and 18. These ranges depend heavily on when puberty starts, how long it lasts, and genetics. But “growing” doesn’t just mean height. Your bones continue gaining density into your mid-20s, your brain keeps maturing until about 25, and certain body parts like your ears and nose change size for the rest of your life.
When Girls Stop Growing Taller
For girls, height growth is closely tied to their first period. On average, girls grow about 7 cm (roughly 3 inches) after menstruation begins, but the exact amount depends on timing. Data from the Fels Longitudinal Study shows that girls who start menstruating at age 10 gain about 10 cm (4 inches) afterward, while those who don’t start until age 15 gain only about 5 cm (2 inches). Earlier puberty means more post-period growth, but it also means reaching adult height sooner.
Girls who begin developing breasts at 8 or 9 typically have about 3 years before their first period arrives, giving them a longer runway of gradual growth before that final stretch. Most girls have reached their full height by 14 to 16, though some who started puberty later may still be adding small amounts into their late teens.
When Boys Stop Growing Taller
Boys generally finish growing between 16 and 18, though some continue adding height into their early 20s in rare cases. The difference from girls comes down to puberty timing: boys typically start and finish puberty later, which gives them a longer period of childhood growth before their adolescent growth spurt even begins. This is one reason adult males are, on average, taller than adult females.
Some boys shoot up quickly at the start of puberty, while others grow at a slower, steadier pace. Both patterns are normal. The key factor is whether the growth plates, the bands of developing cartilage near the ends of long bones, have closed. Once those plates harden into solid bone, no more height can be added. In boys, growth plates in the hand typically fuse around age 16, while the knee joints may not fully close until the early 20s.
What Growth Plates Are and Why They Matter
Growth plates are sections of cartilage at the ends of your long bones (legs, arms, fingers) that gradually produce new bone tissue during childhood and adolescence. As long as they remain open, you can still grow. Once they close and calcify into solid bone, height is locked in permanently. No exercise, supplement, or stretching routine can reopen them.
Growth plates close earlier in girls than boys. Hand growth plates tend to fuse around age 15 in girls and 16 in boys. The knee joint plates, some of the last to close, fuse around 21 in females and as late as 24 in males. This is why some young men swear they grew a little in college: their knee and spine growth plates may still have been slightly open. Doctors can check growth plate status with a simple X-ray of the hand or wrist, which is the standard method for estimating how much growth remains.
Feet Stop Growing Before Height Does
If you’ve noticed that your child’s shoe size seems to have stabilized while they’re still getting taller, that’s expected. Foot growth peaks early in puberty and levels off well before height does. In girls, shoe size typically plateaus around age 12. In boys, it plateaus just before age 14. Peak foot growth actually happens 1 to 2.5 years before peak height growth, which makes a stabilizing shoe size one of the earlier signs that a child has entered the later stages of their growth spurt.
Predicting Final Adult Height
Pediatricians use a simple formula called mid-parental height to estimate a child’s likely adult height. For boys, add 5 inches to the mother’s height, add the father’s height, and divide by 2. For girls, subtract 5 inches from the father’s height, add the mother’s height, and divide by 2. This gives a rough target, though actual height can land a few inches above or below that estimate depending on nutrition, health, and individual variation.
This formula works as a general guide, not a guarantee. Children who are chronically malnourished, who have untreated hormonal conditions, or who take certain medications that affect growth hormones may end up shorter than predicted. On the flip side, excellent nutrition and overall health can help a child reach the upper end of their genetic potential.
Parts of Your Body That Keep Growing
Height may stop, but not everything does. Your ears grow roughly half a millimeter per year for the rest of your life, driven by ongoing changes in collagen and cartilage structure. Your nose undergoes similar changes. This isn’t the same kind of growth that happens during childhood. It’s a slow reshaping and stretching of cartilage and soft tissue under the influence of gravity and aging, which is why older adults tend to have noticeably larger ears and noses than they did in their 30s.
Your Bones Keep Building Until Your Mid-20s
Even after you’ve stopped getting taller, your skeleton isn’t done. Bone density, the mineral content that makes bones strong, continues increasing into young adulthood. Women typically reach peak bone density around age 22, while men don’t peak until closer to age 27. This means the years between 15 and 25 are critical for building the strongest possible skeleton, which pays off decades later when bone density naturally begins to decline.
Weight-bearing exercise and adequate calcium intake during this window have a lasting effect on bone strength. Think of it as filling a bank account: the more you deposit during your teens and early 20s, the more reserves you have when withdrawals start later in life.
Your Brain Matures Until About 25
The front part of the brain, responsible for decision-making, impulse control, and long-term planning, is one of the last brain regions to fully mature. Development in this area continues throughout adolescence and isn’t complete until around age 25. This is a key reason why teenagers and young adults often take greater risks, struggle more with impulse control, and weigh consequences differently than older adults. It’s not a character flaw; it’s an organ that hasn’t finished developing yet.
What Influences When Growth Stops
Genetics is the biggest factor, accounting for roughly 60 to 80 percent of your final height. But several other variables play a role in when growth plates close and how much height you ultimately gain.
- Puberty timing: Earlier puberty generally means earlier growth plate closure and a shorter total growth period, though the growth spurt itself may be more intense.
- Nutrition: Chronic malnutrition or severe caloric restriction during childhood can stunt growth. Adequate protein, calcium, vitamin D, and zinc support normal bone development.
- Hormonal conditions: Growth hormone deficiency, thyroid disorders, and excess cortisol (the body’s stress hormone) can all delay or limit growth. Cortisol, in particular, suppresses the signals that drive bone lengthening while also delaying the natural aging process of growth plates, creating an unusual pattern where growth is slow but the window stays open longer.
- Chronic illness: Conditions like celiac disease, inflammatory bowel disease, or kidney disease can interfere with nutrient absorption and hormone signaling, both of which affect growth.
- Sleep: Growth hormone is released primarily during deep sleep, which is one reason pediatricians emphasize consistent, adequate sleep for growing children and teens.
Signs That Growth Has Stopped
The most reliable indicator is reaching the final stages of puberty. For girls, this typically means 2 to 3 years after the first period. For boys, it’s when facial hair has filled in and the voice has fully deepened. A stabilized shoe size is an earlier clue. If height measurements taken 6 to 12 months apart show no change, growth has likely finished. The definitive answer comes from a hand or wrist X-ray, which can show whether the growth plates have fully closed.