A phallic cucumber grows on the vine

When Does the Penis Stop Growing? Later Than You Think.

If a boy’s still growing, his penis is probably still growing too.

Sep 14 2021, 1:25 PM

First of all, it doesn’t matter how big it is. Parents should broadcast this to teenage boys and check themselves if they’re wondering how well-endowed their toddler will be. Happiness is more important, and a big or small penis does not guarantee happiness or a lack thereof. Besides, when it comes to sex, proportions matter far more for attractiveness than size (but, maybe hold off on that fact until they’re in their twenties). That said, many still wonder how big it will be, scientifically speaking, and find themselves asking “when does a penis stop growing?” The answer depends on your personal puberty trajectory, according to Judson Brandeis, MD, a board certified urologist in San Francisco, California. 

When Does a Penis Stop Growing?

The penis goes through its most rapid growth during puberty as a result of a testosterone boost. Most growth occurs between the ages of 12 and 16. But that doesn’t always mean you’ve hit your peak by that point. Some boys experience puberty and additional penis growth into adulthood. For most, it stops at age 18. But there are reports in some men, though few in number, who experience growth in their penis size in their early 20s.

“The penis begins growing when a boy reaches puberty and his testosterone levels begin to spike. The penis achieves its full length and girth at the end of puberty,” Brandeis says. The testicles start growing much earlier at around 8 years old, also continuing until the end of puberty, Brandeis says.

Penis growth starts in the early teens, and most men reach their penis potential in both length and girth at around the same time they hit their height peak. So some late bloomers can hold hope that the best is yet to come. 

What’s the Average Penis Size? 

If you’re wondering whether you’re well-endowed, the average penis size is 5.61 inches when erect and 3.12 inches flaccid. The average girth is around 4.59 inches erect and 3.67 inches flaccid.

For years, studies have shown that the average penis size was 6.2 inches erect. But it turns out that in much of the research, men had been exaggerating their lengths so often that it led to this common misconception. When researchers began to measure the penis size themselves instead of just asking, the numbers skewed downward.

And those old wives’ tales about the link between penis size and the size of hands and feet are, not surprisingly, complete bullshit. (The length of your ring finger may be a better measure.)

The Ideal Penis Size for Performance

Men often think their penises are smaller than average. And whether or not it’s true, this can make them overly self-conscious. But if you’re worried about how a smaller-than-average penis affects your game in the bedroom, you can relax.

In a survey of 52,031 men and women, 85 percent of partners reported being satisfied with their man’s penis size while only 55 percent of men thought their penis was large enough. The bottom line: Most men need to be a little more proud of what they’re packing.