How to measure penis size

People measure their height and weight, so why not measure penis size?

In 2023 there are still a lot of clickbait articles and bogus data on penis size, which is unfortunate. We try to correct this by looking seriously into the data on penis sizes. This site provides up-to-date, accurate information about penis matters such as how to measure yourself, what are penis size averages of length and girth, and even a scientific look at penis enlargement. 

Right and wrong ways to measure penile dimensions

There is a wrong way to measure penis length so do not despair, perhaps you’re mismeasuring it.

It is quite a common mistake and very simple to correct.

Men make when errors measuring penis size

Before you begin and after you measure your penis size remember that penis size is not that important.

Most men’s penis size is expectedly average.

Common sense

Knowing your penis size is a good idea. Most men do now know what is the correct way to measure penis dimensions and after measuring it incorrectly men may feel self-conscious about their penis size. This may be damaging to their self-esteem. Self-esteem problems lead to a loss of confidence and even diminished sexual appetite and performance. Therefore it is important to know how to measure penis size, both length, and girth (circumference) properly, the way medical professionals do it. The method of this measurement is used in urological research.

Measuring penis size correctly will help you to feel more confident. It will also help you find condoms for your size. 

Measuring penis size runs into the problem of consistency as the strength of the erection changes considerably depending on many factors. Your penis size will change, even throughout the day. If you measure your erection size and it does not feel like the erection you achieved is the real size, you could be right. Sometimes you may go into a sexual encounter and surprise yourself thinking, “hmm, usually my erection is bigger”. This is very likely to be the case.

Look into what interferes with the strength of the erection.

If you want to know about average penis sizes, including statistical analysis of over 40 studies for over a century, and to learn about differences between people visit the Average penis size by ethnicity page. You can also learn about how penis size impacts Female sexual satisfaction.

Penis size may change through conscious efforts, so it is worth exploring penis enlargement science and all the methods associated with it.

Is there a correct way to measure penis size?

Yes. There is only one proper way to measure penis size, the method used in sexual and urinary medicine. If you want to compare against averages or just to be aware, it is best to use this method.

  • Don’t stress about measurements, researchers found that even the way erection is achieved alters the results.
  • Penis size is not in any way a defining characteristic for a human being, it’s not even that relevant to female sexual satisfaction or sexual selection.
  • Knowing your size is important because you can find a better-fitting condom and feel safer.
  • Remember that you as a person, as a male are not defined by your penis size
  • Remember that a gorilla that weighs twice as much as a human has a penis length of 1.5 inches or 3cm so you beat a very manly primate by default.
  • A comfortable private environment
  • An erection
  • A piece of string
  • A ruler

Prepare a ruler or a tailor measuring tape. If it is one of those sharp metallic rulers, try not to stab yourself with it. Try not to slice half of your cock off during the process.

If overly eager and/or prone to funny injuries prepare and practice a cover story for the accident and emergency room.

Getting an erection

Make sure your penis is erect and straight, the steps you take to get the desired effect are no concern of ours, but again try not to do anything overly creepy.

We’d put a few humorous suggestions of what not to do (such as dressing up in a lycra superman costume and taking Viagra whilst on a subway train at peak hour), but we realize that some people will react with enthusiasm and go “well, that’s a thought”. So we recommend approaching penis size measurement with both touches of humor (pun intended) and with an empirical thirst for truth.

Once your penis is erect and straight (if you have a bendy penis, that’s no problem, use a flexible measuring tape and follow the procedure, you may need to bend the measuring tape according to the curvature of your penis. Place the measuring device on top of the penis, measuring tape, or ruler facing up. Penis length is measured from the base of the shaft (where your penis meets the groin) to the tip of the penis.

Measuring penis length

To measure penis length press the ruler into the groin over the top of the penis
  • Measure from the pelvic bone to the tip of the erect penis along the top
  • Press the ruler into the groin to compensate for the layer of fat and pubic hair. The most common error that men make when measuring penis length is not pressing into the groin.
  • Position the ruler perpendicularly to the body (as the angle at which you measure will make a difference)
Pressing the ruler at an angle.

The angle at which you measure will have an impact on the measurements, so press the ruler perpendicularly into the groin, so that it is at approximately a 90-degree angle.

Pressing into the groin compensates for a layer of fat and pubic hair.

Bush size and groin fat that you have can have a massive effect on the result. Therefore we recommend placing the ruler/measuring tape right at the base of the shaft, pressing firmly into the groin (and again we remind you, try not to stab yourself in the process!). The length from the base of the shaft to the tip of the penis is your penis (cock, dick, willy) length.

Pressing hard into the groin for maximum length is justified by the fact that some men have more fat and more pubic hair. The difference could be significant. Shaving pubic hair and losing groin fat through exercise or liposuction will visually increase the penis length perception, and practically speaking, size.

Measuring penis girth/width/circumference

To measure girth wrap the string/measuring tape over the widest part of the penis
  • You may need to measure the head of the penis (the glans) and the shaft separately.
  • Once the penis is erect, measure the organ’s girth. Try to measure the girth of the penis mid-shaft, where it is of the same thickness.
  • Wrap a measuring tape across the widest part of your penis. If the penis head is wider than the shaft, measure it separately. This is relevant because some condoms are flare shaped, wider at the top, with more room at the end of the condom.

If you don’t have a measuring tape, use a piece of string or cloth. Wrap the string around the widest part of your penis, mark the beginning and the end and then place it on top of a ruler. Read and record the measurements.

Some men will have larger heads of penises than others but measuring them will not give a reliable estimate since the figures will not be the same, so try to measure the penis girth at mid-shaft, not at the head.

If you don’t have a flexible measuring tape that the tailors use to measure dimensions, take a string and wrap it around your penis, mark the beginning and the end and then measure it with a ruler. This will give a very accurate measure of the penis girth/circumference. When measuring penis girth, try not to strangle your little friend.

If the head of the penis, the glans is much larger than the shaft, you may want to invest in flare-shaped condoms, which will be more suitable for your particular penis size.

Everybody lies or why you shouldn’t trust self-reported penis measurements

Penis size is often the subject of embarrassment for men. Incorrect measurements that usually come from self-report studies are often picked up by bloggers and media, who misrepresent the findings as having empirical value.

Even when being truthful, many men mistake how penis size should be measured and measure it incorrectly. By doing this men distort their perception of their own and the average penis size.

Don’t trust studies that mention self-reported penis measurements.

Distorted perception of penis sizes

Porn, web forums, magazines, and other media sources distort the perception of penis sizes. 

There are numerous topics on internet forums and in men’s magazines where men can openly (although mostly anonymously) discuss their cock sizes, dick sizes, shaft lengths, willy girths, and their little friends.

It appears that penis size is very important, at least to men who discuss them. Some comments appear to come from 12-year-olds who have just hit puberty (judging from the grammar and earnestness alone), who claim to have a thick 8-inch one.

Reality and statistics suggest this is, in fact, a wild exaggeration. So don’t be intimidated when others mention elephant-sized genitals.

When someone mentions having a willy of a size to choke a dozen donkeys it is best to sigh or ignore it.

We have established the average penis size after analyzing over 40 studies and the results are relatively accurate. Our findings for the average penis sizes are directly comparable to the measurement method described in this guide.


Porn also distorts men’s perception of penis size and it is unwise to think that the penis size that is shown in porn is in any way average. Similarly, the heights of NBA players would not be good indicators of average height. You don’t watch an NBA game and think that it is what men should look like. People doing specific jobs are selected because they have an advantage but extreme sizes are in the clear minority, in both height and penis dimensions.

After measuring the penis size, length and girth

We understand that we live in the digital age of Twitter and Facebook and youtube. However, consider yourself warned against posting this information about the fruit of your scientific adventure online. Instead, find the correct condom that fits you.

Problems with gathering data on human male penis size

“Usually it is bigger”

Anonymous/every male

The same male can measure the penis in the morning and in the evening to find that the measurements differ. It is completely fine.

Natural minor variability in size occurs due to arousal level, time of day, room temperature, frequency of sexual activity, and other factors.


If you attempt penis enlargement techniques such as Jelqing or using penis pump devices – try to measure your penis sizes using a consistent method, in a consistent setting.

Also be aware that self-reporting penis size, as in anonymously measuring own penis dimensions and submitting the data to websites or research is largely inaccurate and should not be relied upon for comparison.