When Does the Penis Stop Growing? Everything You Need to Know

Worrying about your penis size? You’re not alone. So when does the penis stop growing? 

If you’re still navigating your teen years, it’s possible your penis may continue to grow a bit more. Most penis growth happens during puberty, but there’s no definitive end date for when a penis stops growing. Some men even experience growth into their early 20s. 

Below, we dive into penis growth and what the research says about average penis size.

What age does your penis stop growing? There’s no exact age, but typically it’s around the end of puberty.

Puberty is the period during adolescence when the male body goes through various physical changes due to rising testosterone levels. It typically starts between ages 9-14 in males.

Typical changes include:

• Testicle and scrotum enlargement

• Rapid growth spurt

• Penile enlargement, in length and girth

• Pubic hair growth

• Acne

• Deepening voice

• Onset of wet dreams

Penis growth generally begins in the early stages of puberty with the biggest increase around ages 12 to 14. The penis eventually progresses to its adult size at the end of puberty, which usually happens between ages 14 and 18.

Some men might continue to have a small amount of growth in height and penis size into their early 20s.

Penis size generally doesn’t change throughout adulthood but can decrease slightly in older males.

Read more about penis shrinkage with age.

Medical Conditions that Can Lead to Loss in Penis Size

Health conditions like diabetes can affect circulation, making it harder for blood to reach the penis. This might impact the size or quality of your erections. 

Additionally, Peyronie’s disease causes a curve in the penis that can lead to a smaller erect penis size, depending on the severity of the curve.

Most research shows that the most significant growth in penis size happens right after birth and during early adolescence. 

A 2018 study in China, involving nearly 3,000 boys, recorded the following stretched flaccid penis sizes by age:

Learn more about measuring your penis length.

Many men worry about whether they “measure up” below the waist, even when they’re perfectly average. Interestingly, most men seeking penis enlargement surgery already fall within the average size range.

So, what’s the actual average penis size? That’s tricky to pin down because measurements depend on factors like:

• Whether the penis is measured from the pubic bone or bottom of the penis

• How much researchers compress the fatty pad above the pubic bone

• Whether the penis is flaccid, stretched, or erect

• Self-reported measurements (which tend to be exaggerated)

• Representation across ethnic groups and geographic areas

Most current studies likely overestimate the average length, especially those relying on self-reported data. 

According to a 2020 review, most men think the average length of a penis is about 6 inches. That’s probably because many self-reported studies suggest an average size of about 6.2 inches. 

The same review, which analyzed 10 studies on erect penis length, found the average to be between 5.11 and 5.5 inches. For stretched flaccid length, the average was about 5.11 inches. 

Researchers point out that the true average is probably closer to the lower end of this range since men with smaller penises are less likely to volunteer for these studies. 

Learn more about average penis size.

Girth is the measurement of the circumference of the penis or how thick it is.

In a 2021 study, 4,685 young Italian men were given instructions on how to measure their penis size. The researchers reported the following average sizes, but keep in mind these are self-reported figures and are likely exaggerated:

• Flaccid penis length: 9.47cm (3.7 inches)

• Flaccid penis circumference: 9.59 cm (3.8 inches)

• Erect penis length: 16.78 cm (6.6 inches)

• Erect circumference: 12.03 cm (4.7 inches)

The study didn’t include men with:

• A congenital or acquired penile abnormality

• Previous surgery

• Erectile dysfunction

Contrary to popular belief, size doesn’t appear to be a top factor in sexual satisfaction for women. 

Things like emotional intimacy, communication, and sexual technique matter much more. 

An older study from 2006 found 85% of women were happy with their partner’s size, while 45% of men wished their penis was bigger — a clear mismatch in perception. 

Another study from 2015 showed that females preferred only slightly above-average penis sizes. 

Concerns about penis size are often influenced by media, social comparisons, and myths surrounding sexual function.

If you’re feeling anxious about your penis size, consider speaking with a urologist, therapist, or other health professional who can provide you with clarity and reassurance.

Learn more about what penis size women prefer.

The following factors can influence when your penis starts and stops growing:

• Genetics. Your genetics largely determine your androgen hormone levels, penile length, girth, and timing of growth. Additionally, your Y sex chromosome is what causes male genitalia to develop in the first place.

• Hormones. Testosterone levels play a central role in pubertal changes. Insufficient levels can lead to delayed or reduced growth. Conditions like hypogonadism (low testosterone) may result in a smaller adult size penis or other developmental concerns.

• Health and nutrition. Poor nutrition or chronic illness during childhood or adolescence may affect hormone levels, puberty development, and penile growth. 

• Lifestyle factors. While lifestyle doesn’t directly impact size, habits that support overall health like regular exercise, adequate sleep, and a balanced diet are important for general physical and sexual health.

Worrying about penis size is common in adolescents and adults. Concerns can lead to anxiety, self-consciousness, and even relationship issues. 

An intense focus on the size of your penis, despite being in the average range, is called penile dysmorphophobia disorder. 

If size worries are weighing on you, therapy or counseling might help. 

Medically, a micropenis refers to an unusually small penis present at birth, caused by hormonal or genetic factors. It’s rare, affecting about 3 in 20,000 male newborns.

How small are we talking? In adults, a stretched micropenis measures 3.7 inches (9.3 cm) or less. 

Treatment options for children include testosterone therapy, either through injections or gels. If these aren’t effective, the only other option is surgery. But it’s risky due to the potential for complications. 

If you have a micropenis or a smaller-than-average penis, it’s still possible to have a fulfilling sex life. Find out more in our blog on sex positions for a small penis. 

There’s a lot of misinformation out there about penis growth and size. Let’s dispel a few myths:

• Viagra and erection medications make your penis bigger. Viagra and other erection medications make it easier to achieve an erection, but they don’t increase your penis size.

• Supplements and creams can make your penis bigger. Penis growth supplements and penis enlargement products often lack reliable evidence and can even be dangerous.

• Masturbation increases or reduces size. Masturbation doesn’t affect penis size in any way.

• Penis size is the most important factor for pleasurable sex. Most anecdotal evidence suggests that technique and emotional intimacy are more important than penis size alone.

It’s a good idea to seek medical attention if you or your child are dealing with any of the following:

• Delayed puberty. If puberty hasn’t started by age 14, hormonal or developmental issues may be at play.

• Micropenis. If detected early, hormone therapy might help with growth. A pediatric endocrinologist or urologist typically oversees these cases.

• Sexual dysfunction. If you have symptoms of erectile dysfunction (ED) or problems with ejaculation. It’s a good idea to see a healthcare professional for advice. Penis pain during sex also warrants a trip to the doctor.

Priaprism, a prolonged and painful erection is an emergency that requires immediate medical attention.  

Learn more about common penis disorders.

The male penis generally stops growing around the end of puberty. For most men this is around the late teen years or early 20s. 

Let’s recap what we know about penis growth and size:

• Penis size varies a lot from person to person. Many factors influence penis size like your genetics, nutrition, and overall health.

• Many men report being unsatisfied with their penis size. Surprisingly, most of them fall within the average size range. 

• Women seem to agree that penis size isn’t a big deal. Other factors like emotional connection matter more for pleasurable sex. 

Worried about whether you measure up? Consider talking to a healthcare professional like a urologist. They can provide reassurance, education, and evidence-based advice.

And if your penis size worries are making it tough to enjoy sex or achieve erections, a therapist might be able to help ease your anxieties.