This article is more like a course in geometry than an article in sexology, but it was important to clarify the vocabulary. Many men get tangled up in the measurements when they want to compare the size of the penis to the numbers they find on the internet.

## What is penis length: how to measure it correctly?

The length of the penis is the size of the penis at rest or erection, as considered by science or medicine. To find the exact size, proceed as follows, if you are at rest: stand upright, rest your penis in the palm of the hand parallel to the ground. The penis should be placed simply in the hand and should be well perpendicular to your body. Take a rigid ruler and place one end against the pubic bone. This means that you can slightly break the rule, if you have a little fat on the pubis. It does not help to cheat to gain a centimeter, so no need to press too hard. If you are erect, proceed in the same way, except that you must arrange (depending on the inclination of the erect penis) so that the penis is also parallel to the ground, so well at right angles to your body. Sometimes you have to push the rod down.

You have a penis in the average if your height is 13 to 15 cm. In France, according to studies, the average penis size is about 14 cm in erection. Of course, the size of the penis varies according to age, especially if puberty is not over. Old age can also decrease the size of the penis or Peyronie’s disease.

## What is the circumference of the penis: how does the circumference measure?

The circumference is the measure of the turn of the penis. This is the measurement that reflects the thickness dimension of the penis, just like the diameter. These two dimensions come back to practically the same thing, except that they are not calculated in the same way. The circumference is the length of the turn of the penis if it were flat.

Basically, if you take a string, you do a penis ride with the string. As you unfold the string and lay it flat on the table, how long is the string unrolled? This length is the circumference. The disadvantage of circumference is that the measurement obtained does not speak to many people. For example, the average circumference of the erect penis in the world is 12.8 cm. It is difficult to visualize what a circumference of almost 13 cm represents. The advantage of circumference is that it is the most accurate measure if you really want to know the thickness of your penis. You will understand why by reading the explanation about the diameter.

The other advantage of circumference is that it is simple to measure. Do as shown with the string method, but if you have a tape measure it is even better, easier and more accurate. Wrap the tape around your penis at rest or erection and you will know your circumference. If the thickness of the penis is not regular, ie you have the larger base or a tassel bigger than the rest of the penis or sometimes the middle part of the penis is wider than the rest must be measured in the middle of the height of the penis. Others prefer to average between two measurements, but normally, this is not how we take the reference measurement.

## What is the diameter of the penis: how to calculate the diameter?

The diameter of the penis is the other measure of penis thickness. In fact, the diameter gives rather a measure of width, while the circumference gives a measure of thickness. Both diameter and width are 2-dimensional measurements, while circumference and thickness give a 3-dimensional volumetric measurement. The diameter corresponds to the radius of a circle.

Men often prefer to talk about the diameter of the penis because the result is more meaningful. It is easier to imagine what the width is, and the number visually indicates the size of the penis. On the other hand, measuring penis diameter is not as simple as you think. The diameter is the length that we get if we cross a circle through the center. As one can not cut the penis in two, it is necessary to measure the diameter of the outside. This corresponds to two imaginary points which are at the ends of the penis, in its width.

If we really wanted to measure the diameter correctly, we would have to take a caliper. It is the only reliable diameter measuring device, because thanks to these two sliding parts, it can precisely come jam the rod. If you measure the diameter at sight of the nose, you will be wrong in the measurements because the cylindrical aspect of the penis distorts the impression because of the perspective. It is difficult to really determine where the edges of the penis are.

The other way to know the diameter of a cylinder, a circle or a penis is by using a mathematical formula. This one is very simple and everybody knows it. We must use the number pi (π). Remember, the number pi is 3.1416. By knowing the circumference of your penis, by measuring it easily as indicated above, you will obtain your diameter. Take the circumference and divide it by pi. For example, if we take the average circumference of the penis in the world which is 12.8 cm, here is the calculation: 12.8 ÷ 3.1416 = 4! The average diameter of the penis in the world is therefore 4 cm.

You can verify by doing the calculation through the circumference, and roughly measuring with a ruler in front of the penis, you will see that you will be not far from the same number, but not very accurately.

The only drawback of measuring the diameter in general is that not all penises are 100% cylindrical. Sometimes, men have a penis a little flattened and therefore the penis is wider seen from above than on the side. Also, the cylinder is not perfect. The big dorsal vein is strong in some and therefore, if we cut the penis in slices, we would not have perfectly circular slices. We would rather see a circle with a slight blister up. That’s why once again the diameter is not really the most accurate way to know the size of the penis.

## Size, width and thickness of the penis, what is it then?

We have already responded by browsing the previous steps. The term “size” simply refers to the notion of size when we speak of the width of something. It is a generic term that evokes the width of the penis.

The width precisely is the dimension that separates two points in the smallest direction (compared to the length, which is in the longest direction). The width corresponds to the dimension obtained by calculating the diameter. It is a dimension that does not take into account the volumetric aspect.

The thickness is the same as the width but taking into account the volumetric aspect. The thickness is calculated by measuring the circumference.

## What is the volume of the penis?

Finally, this measure is not often used, but sometimes we see some sites that talk about the volume of the penis. To represent mentally what the volume measure can be, imagine a bottle of water (it’s almost like a penis). Imagine a bottle of water a liter, you realize that it is much larger than your penis (normally …). Well, 1 liter corresponds to a volume of 1 cubic decimetre (1 dm3 or 1000 cm3). Cubic centimeters are calculated by taking the radius squared x pi x height. As a reminder, the radius in our case corresponds to the calculation of the diameter explained above. We therefore have all the necessary measures to calculate the volume.

If we take the example figures based on the average of the penis circumference, here is the calculation. We saw that the average circumference was 12.8 cm and the diameter was 4 cm. If you do not know how to make 4 cm in diameter, read the paragraph about diameter (recall: 12.8 ÷ 3.1416 = 4). So the radius is 2 (since it’s half the diameter). And also remember that the average erect penis length we took was 14 cm.

To calculate the volume, make: 22 x π x 14 = 176 cm3.

We remember that 1 L = 1000 cm3.

So with an average of about 178 cm3, this corresponds visually to a bottle of about 20 cl.

Why does this volume seem too big? Because this measurement takes into account a perfect cylinder and does not take into account that the penis is not a cylinder where the end is flat. The penis ends with the glans, so this part is smaller and therefore the volume is smaller. If we wanted to get closer to a more precise volume calculation, we would have to calculate a cylinder on the part of the penis without the glans and add the calculation of a truncated cone for the volume of the glans. Not to mention the fact that the penis is not regular.

Another way to calculate the volume is to make a mold of your sex, then fill the mold with water and then measure the volume of water that could hold the mold.