Penis Size Information

How big your penis is when it's soft is no kind of guide to the size it will become when it's erect. By the way, in case you're wondering, the average size of an erect white penis is 5.9 inches, but many hundreds of millions of men in the world are much larger or smaller than this.

About penis size

Here are the facts about penis size:

From a survey conducted by The-penis.com in 2003 on over 1500 men, the results are as follows:

  Summary:

By average it means the mid point of the male size range. So half of all men have an erect penis shorter than 5.9 inches, and half have one over 5.9 inches. The full details make interesting reading. For example, 12.5% of men are less than 5 inches when erect, and about 2% are less than four inches when erect - that's 2 men in every 100, or about 2 million men in the US alone. And most of these men are married and many have kids. Conclusions? A small penis is not important - unless it's important to you. Penis size is a male issue, not a female one.

(In case you're wondering, only 7.5% of men are larger than 7 inches when erect, and only about 1 in a hundred is over 8 inches when erect.)

Complete results in detail:

With over 1,500 responses, these are the complete results of the survey for the white racial group respondents. All averages are medians:

1) Average erect penis size

Average penis length when erect = 5.9 inches

Average penis girth when erect = 5.0 inches 

2) Flaccid (soft) penis size

Average penis length when flaccid = 3.4 inches

Average penis girth when flaccid = 3.9 inches

Penis structure

Despite the endless array of penile shapes and sizes, all penises have a similar structure. This is shown in the diagram below.

Illustration from Intactivism. Used by permission.

The penis is not a muscle, though it has muscle fibers along its length. It's actually made up of three chambers of elastic tissue which can expand when blood flows into them to about three times the volume they normally occupy. The rise in blood pressure is caused by the veins at the base of the penis constricting so that blood flow out of the penis is less than blood flow in, and the result is an erection. The three chambers which fill with blood can be seen in the cross-section diagram above: two lie above the urethra and one below it. 

The foreskin is about as variable as the penis: some are long and taper beyond the end of the glans, some are short and end halfway down its length. In all cases, though, the foreskin is designed to move freely back and forth over the head of the penis - the glans - during intercourse. There are several theories about why this happens, but one of the most convincing is that the movement of the foreskin provides a seal between the penis and vagina during thrusting, so that the woman's natural lubrication cannot leak out of the vagina during intercourse. Biologically, it's all about having the most efficient reproductive system possible. There is an excellent animation of the movement of the foreskin, which mirrors the movement that uncircumcised men may use to masturbate, on this site, though it is often temporarily down because of the high bandwidth. It does make interesting viewing, though. (It takes quite some time to load.)

The shape of the head of the penis is designed to provide enough stimulation to the nervous system to provoke an  ejaculation orgasm during intercourse. The coronal ridge and foreskin in particular seem to be important elements in the nervous control of ejaculation, stimulating the reflex of ejaculation when they, or their nerve endings, have been subjected to sufficient pressure and movement. Of course, one of the incentives to have sex in the first place is the extreme pleasure that results from the stimulation of the glans during thrusting. But the most sensitive part of the penis head is often just under the head, where a band of skin called the frenulum attaches the foreskin to the underside of the glans. Sadly this may be missing in men who have been circumcised.

One of the things that parents often do not realize is that the foreskin of a baby boy is not designed to move backwards over the glans. The foreskin adheres to the glans until a boy is between 5 and 15 years of age, and any attempt to force it back before it separates naturally can result in painful tearing and scar tissue formation which later makes the glans uncomfortably sensitive. 

Along the underside of the penis you'll see a thin ridge of skin called the raphe. This is where the penis sealed together along its transformation from a flat plate of tissue into a hollow tube during a baby boy's development in the womb. Sometimes this process goes wrong, and the seal doesn't develop all the way along the length of the shaft, leaving men with a urethral opening some distance back from the head of their penis. This condition is called hypospadias. It's often accompanied by a twisted shaft, a head shaped like a huge flat mushroom, and one or two other structural differences.

The muscles fibers that run along the length of the penis are responsible for the variation in penile size that occurs between hot and cold conditions, and for the shortening that some men see when they are nervous or excited. The effect is different in each man, but because these muscles fibers are an extension of the muscles in the scrotum, the more your balls shrink up in the scrotum when you're cold or anxious, the more likely you are to have a penis that varies considerably in length - another reason why talking about an average length is probably not very helpful! 

This picture from The-penis.com Foreskin Restoration page shows you the structure of an uncircumcised penis with the foreskin rolled back. This site has a lot of detail about the process of foreskin restoration - something which an increasing number of circumcised men are trying. The skin of the penis - like the skin anywhere on the body - responds to a gradual process of stretching by increasing in length, and with sustained stretch over a period of time, it is possible to regenerate a foreskin - though it is missing the particularly sensitive nerve endings present in the foreskin at birth.

But why go to the trouble of stretching a new foreskin out of a circumcised penis? The answer is probably different for each man who does it. One common reason is appearance -  a guy simply prefers the look of an uncircumcised penis and wants it like nature intended. Another good reason is that sensitive skin of the glans is, like the inside of the mouth, made of a special type of skin called mucus membrane, which was not designed by nature to be exposed to such things as, in the case of the penis, the rubbing of underwear. The glans is naturally protected by the moist inner lining of the foreskin, which is also a mucus membrane. Without a foreskin, the glans can become rougher, harder and sore. It can also be extremely sensitive to the rubbing of clothing and to the cold - many circumcised men find they have great difficulty with this sensitivity. (So, as it happens, do many uncircumcised men, for example when they masturbate. The difference is that they can roll their foreskin back over their glans to protect it when they are not having sex or masturbating.)