When babies are born, “It’s a girl” or “It’s a boy” used to be the things parents were waiting to hear from the doctor or mid-wife. Now, parents have the option of finding out the biological gender of their baby long before birth. What they’re waiting to hear is “your baby is healthy!”

A number of years ago a parent wrote us with a question about the size of her baby‘s penis. Dr. Greene answered it in detail in a Q&A titled Penis Size Defined and we created an FAQ that was more generalized titled Penis Size. These two posts were specifically addressing issues of penis size in babies and have nothing to do with penis size during puberty.

Imagine our surprise when boys going through puberty found our post on “Penis Size” (remember, it’s an FAQ derived from a much longer article) when searching for information about penis size during puberty. And even greater surprise when they started posting questions about their own penis size during puberty to the comments section.

Our Response

We read and moderate every comment before it goes live on That means a live person reads the comment to determine if it meets our guidelines before it is posted. We encourage people from multiple points of view to express their opinions. We encourage real questions from readers. But we don’t allow comments that use pornographic or sexually suggestive or explicit language, contain false statements that may hurt others, or comments that disparage others, including name calling and bullying.

In our opinion, many of the questions from teenage boys asking about their penis size during puberty were genuine and deserved to be posted. The ones that didn’t fit our criteria, we rejected. But clearly, this is a topic where boys are looking for answers.

Scientific Studies on Normal Penis Size During Puberty

Dr. Greene did a recent review of the scientific literature on normal penis size throughout puberty. The studies he found were old, had a small sample size, were contradictory, or were for a particular ethnic group. He was surprised to find no recent study with a large enough sample group and consistent methodology to be considered definitive. What he did find varied wildly. In some studies there may have even been national pride bias.

As the Executive Producer of the site, I still felt a need to address the issue, so with Dr. Greene’s encouragement, here are my opinions. Please note: I am not Dr. Greene and I am not a doctor. Keep that in mind when reading my post, comments and replies.

My Thoughts on Normal Penis Size During Puberty

Reading the comments submitted by readers prompted my doing my own online research. I am not a physician or medical expert., but I hope my observations are helpful.

Age – Individuals enter puberty at very different ages. In general, girls younger than boys and there is a disturbing downward trend in the age of onset of puberty by both boys and girls. In general, puberty in boys can start as early as 9 or as late as 14 and still be completely normal. The average age has dropped to 10..

Stage – From the time puberty starts until it is fully complete can be several years. It often takes 3 to 5 years from onset to completion. Penis size during puberty is greatly influenced by the stage of puberty. During this time there are many changes. The Body Book for Boys is a good resource that addresses these changes in detail. The peak age for penis growth is usually 12 to 16 years old – about the same time as the growth spurt in height.

Porn Lies – The men in porn are often not normal. Literally. The images are enhanced. This is true in the beauty industry as well. It’s no wonder we all have body issues. Here’s one of my favorite examples of how images are altered to make them more appealing and to make normal people feel bad about their own bodies.

What We Do Know about Penis Size During Puberty

Before Puberty – The average stretched length of the penis before puberty is somewhere between 2.1 and 2.9 inches*.

Adult – The average stretched length of the adult penis (after puberty is complete) is between 4.6 and 5.8 inches (though a more recent study of 6200 boys, mostly white, from Bulgaria, put the average at 3.1 to 4.3 inches. There’s a lot of variation between studies!)

During Puberty – It depends.

Penis growth depends more on Tanner Stage than it does on age.

When to Freak-out – Okay, it really should be, when to see your doctor, but I did get your attention.

If you worry that your penis size during puberty is not developing normally, it’s really okay to see your doctor. You don’t need an excuse, but a great time to bring this up is during an annual check-up. During puberty, you will normally have your physical exam without a parent in the room, so this is a very easy discussion to have with your doctor.

Here are some sample questions:

  • What stage of development (or Tanner Stage) am I currently?
  • Is my penis within the normal size for my stage?
  • If I continue to progress at this rate, in your professional opinion, how large will my penis be when I reach adulthood?
  • Am I normal?

*How to Measure Penis Length

We get a lot of questions about flaccid length verse erect length. Neither is preferred in the medical literature when discussing penis length. The standard is stretched penile length.

To measure your penis size, stretch the penis gently and measure from the bone at the base all the way to the tip. Be sure to depress the surrounding fat pad to get all the way to the base. Using a wooden, metal or ridged plastic ruler is helpful to be able to depress the fat pad and get an accurate measurement.

What Can I Do to Increase My Penis Size?

That is a great question. It’s one many (most?) guys ask at some point.

According to experts, supplements, ointments, creams, etc. don’t work. Stretching can help a little, but sounds more like torture than a medical treatment and has potential side effects that outweigh the potential gain.

Surgery can be effective, but is rarely warranted.

What can help?


It turns out overweight men appear to have smaller penises than normal weight men because part of the shaft is hidden by fat.

If you’re overweight, consider all the health benefits of a healthy diet and getting physical activity. Having more of your penis showing may seem like a big deal (pun intended), but it’s just one of many outcomes of having a normal weight – all positive. Well worth the effort.

Bottom Line on Penis Size

If you are reading this because you are concerned about your penis size during puberty, it’s likely because you have one of two concerns – what the guys in the locker room think or your ability to have a meaningful sex life.

Here’s the secret – people are more concerned with how you treat them than your size. If you genuinely make another person feel special (not a manipulation of their feelings with flattery), your love life will be fine. Concentrate on becoming the kind of person whom others want to be around — interested in them, kind, funny without drawing attention to yourself, empathic, considerate.

If what you’re interested in is a lifetime of happiness, then forget about current peer pressure and become the kind of person another person wants to be with — even if it doesn’t make you the boss of the locker room now..


We are taking an unprecedented path on this subject. We are not going to accept comments from boys asking if their penis size during puberty is normal or not. After all, the answer is in the post above.

If you have comments and / or corrections to this post please submit them. I would be happy to engage in a discussion about this topic. I’d also love to hear from readers about our approach to this topic. Is the information helpful? Did we offer enough information? What’s missing?

One More Thought on Penis Size During Puberty

It’s really normal to have questions about what’s happening to your body during this time of massive change. Keep searching for answers. Keep reading. And seriously, don’t freak-out.

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Cheryl Greene Co-founder & Executive Producer of

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