Penis size investigation

Extract from the “does size matter?” Ebook

Penis length investigation

Measurement methodologies

There are several ways to measure the length of a penis. That’s why it is very important to agree on one unique measurement procedure in order to be able to compare different penis sizes. Ideally, it would be perfect if a worldwide penis measurement protocol existed. However, today, many penis size length found in medical studies or Internet have been obtained using different measurement protocols. So, we cannot compare all penis length sizes from all the penis size studies. By the way, it is useless to measure flaccid or stretched penis size because there is no correlation between the flaccid or stretched penis size on one hand and the penis size in arousal state on the other hand.

How to measure a penis length (bone pressed)

The bone pressed measurement procedure requires a ruler. It measures the length of a penis whatever the curvature from the tip of the glans until the pubic bone. Such a measurement is precise compared to the non bone pressed measurement procedure because measurement is made against a solid wall.  If you want to measure yourself, this is how you have to measure yourself because this is the most precise way to get a measurement. In fact, if you want to see if your penis length change over time it is how you should measure yourself. This measurement procedure allows you to compare your penis length to the Israeli study.

The penis should be measured on the dorsal aspect (on top) from the location where the shaft meets the body until the tip of the glans.

Here is the procedure:

    1. The subject has to get an erection that is not provoked by a nap or a sleep
    2. Stand up
    3. Orientate the penis shaft to be perpendicular to the ground
    4. Place a ruler on top of the penis shaft and press it against the skin until you feel a solid wall. This “wall” is the pubic bone.
    5. Take the measure by really looking above the glans penis. (head of the penis)
    6. Don’t forget to subtract the starting blank space from the ruler.

bone pressed penis length measurement

Figure meslen – Penis Length measurement

Non bone Pressed

This measurement procedure starts from the point where the shaft meets your body without pressing the skin against the pubic bone until the tip of the glans on dorsal aspect. This Measurement is not precise, because it will change depending on the subject’s fat pad length.  Subsequently, a man’s penis will gain or loose length depending on its fat pad length. Gentlemen, the more you gain weight, the more you loose penis length with this measurement methodology..

Many studies like the Wessells study used with this methodology. However, we cannot compare penis sizes using this methodology. Nevertheless, it looks like the non bone pressed measurement is closer to the insertable length in the vagina.

Bone pressed versus non bone pressed

The bone pressed methodology is good to compare individuals but it does not measure the length that can be inserted into the vagina. The fat pad length that is located between the pubic bone and the skin plays a big role regarding length. Difference between the non bone pressed and the bone pressed measurement can be very high because of that. Even with a healthy subject, the difference is noticeable. Two healthy subjects may have a considerable fat pad length difference.

Thanks to the bone pressed measurement methodology you can compare your erect penis to the Wessells study and the israeli study.

The Penis length studies review

We looked into all the penis size surveys and we discovered almost all the penis size surveys are not usable for several reasons.

Most of them are based on men self-reported measurements like in anonymous online surveys. This kind of data gathering is not reliable as everybody can provide fake data. People can also make mistakes. We discovered a funny thing when we looked into penis size studies using self-reported methodology. Their median figures were on average 1 inch (2.54cm) above the penis size studies measured by medical staff. There is like some inflation of the penis size average when the self reported methodology is used. Among the penis size studies that used the self reported measurement, we found the famous Gebhard and Johnson 1979 study. They carried out the last penis size study for the Kinsey institute. A famous institute may have carried out a penis size study, it does not make it «universal truth» for us. We will not review  the surveys based on self-reported measurements. We identified only one private study and two medical studies with measurements performed by medical staff. Only on-site professionals should measure penises for a valid study. This kind of operation is very difficult to setup and those studies are really rare. We can only compare studies with the same methodology.

Secondly many studies measured the stretched penis length. This measurement is totally useless to us for several reasons. Stretched penis measurements cannot help us to know the erect penis size. In fact, other studies prove we can’t calculate erect penis size from the stretched penis size. Every penis grows more or less when it comes to the erect state. A Turkish study found 60% accuracy in forecasting the erect penis length from the stretched length. Furthermore, the stretched penis state doesn’t have any natural sexual function. In other words, we cannot really use it for anything.

At last there is also an issue with erection. An erection has to be provoked for measurement. Either the erection is provoked by drugs injection or naturally. The drugs injection is the best option has it offers the best possible erection quality. In the Wessells study and the Israeli study, the erection state has been induced by drugs.

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  1. Hi
    one comment. in the wessels study he introduced the term “functional penis length”. This was defined as fat pad depth+erect length.
    erect length was around 12,89 cm
    Why do you say that the erect length was taken with the bone-pressed method?
    If the erct lenght was taken with bone pressed method, what is the meaning for defining the functionalpenile length?
    Maybe 12,89 was taken with the NON-pressed method…
    Can you please help to understand?

    Please also have a look at table 1 from “Penile size and the ‘small penis syndrome’ Kevan R. Wylie* and Ian Eardley†. You can find the document easily on the web. Notice that in the table for the wessels study there is the voice “suprapubic fat depth”
    Thanks a lot and my compliments for your site

    1. Here is the extract of the official Wessells study paper

      Tape measurements of the flaccid and erect penis were
      obtained to the nearest 0.5 cm. by 1 examiner. Flaccid length,
      circumference, depth of the prepubic fat pad and stretched
      penile length (fig. 1) were measured immediately after the
      patient undressed to minimize the effects of temperature.
      Measurements were made of the length from the pubo-penile
      skin junction to the meatus, circumference at the mid shaft
      and fat pad depth by pushing the tape into the pubic bone.
      Stretched flaccid length was measured from the pubo-penile
      skin junction to the meatus under maximal extension of the
      phallus. All patients underwent intracavernous injection of
      prostaglandin El for evaluation of erectile dysfunction. After
      a period of privacy and self-stimulation, penile length and
      circumference were measured at full erection. If full rigidity
      was not obtained a mixture of phentolamine, papaverine and
      Prostaglandin El was injected to enhance erection, and measurements
      were repeated. Confidentiality was maintained in
      accordance with criteria of the committee on human research
      at our university.

      So to me, it is clear. they speak about pushing the tape “into the pubic bone”. so it means they pressed the skin at the body-penis shaft junction until they “reached” the pubic bone. If you put a thumb above a tape start you should be able to take such a measure

  2. It is correct. if you read Penile measurements in normal adult Jordanians and in patients, with erectile dysfunction
    International Journal of Impotence Research (2005) 17, 191–195
    “A measuring tape was used to measure the length,
    and the midshaft circumference of the penis. The
    starting point was on the dorsal aspect of the penis
    at its base at the pubic–penile skin junction,
    pushing the prepubic fat pad against the pubic bone
    as described by Wessels et al,3 while the tip of the
    penis was the other reference point”

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