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Measuring penis size correctly.

How to measure penis size, length and circumference

In 2019 there is still a lot of clickbait articles and bogus data on penis size, which is unfortunate. We try to overcome it by looking seriously into the data. We provide up-to-date, accurate information about penis matters ranging from average penis sizes to penis enlargement. Bogus claims may lead to men making misinformed decisions. Therefore it is important to know how to measure penis size, both length, and girth (circumference).

How to measure penis size correctly?

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.

Before you start:

Firstly, don't stress about measurements, researchers found that even the way erection is achieved alters the results.

Secondly, 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.

Finally, knowing your size is important because you can find a better fitting condom and feel safer.

The proper way to measure penis length and girth

 Measuring penis length (summary)

To measure penis length press the ruler into the groin over the top of the penis
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
  • Position the ruler perpendicularly to the body (as the angle at which you measure will make a difference)


Measuring penis girth/width/circumference (summary) 

To measure girth wrap the string/measuring tape over the widest part of the penis
To measure girth wrap the string/measuring tape over the widest part of the penis
  • Wrap a measuring tape across the widest part of your penis. If the penis head is wider than the stem, 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 on top of a ruler. Read measurements.

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

Reporting own penis sizes may be inaccurate

Penis size is often the cause for concern for men. It is simultaneously the main subject of dubious research into male genitalia. 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.

Self-reported penis size measurements in online studies are often exaggerated
Self-reported penis size measurements are often exaggerated

Don't trust studies that mention self-reported penis measurements

We will attempt to challenge these errors and provide a guide for measuring penile dimensions correctly.

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, 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 - best to sigh.

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.

How to take penis measurements - the long version

Safety and ethics

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, prepare, and practice a cover story for the accident and emergency room.

Get an erection

Make sure your penis is erect and straight, the steps you take to get the desired effect is 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 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 humor 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.

Penis length

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 90-degree angle. 

Measure along the top, pressing into the groin

Pressing into 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. 

Penis girth

Measuring at the head and the shaft

Once the penis is erect, measure the organ's girth. Try to measure the girth of the penis mid-shaft, where it is most of the same thickness.

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 your penis is significantly larger, measure it as well. When you look for condoms,  go for flare shaped condoms - with more room for the glans/head.

After measuring the penis size, length and girth

We understand that we live in a 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 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.

 Penis enlargement and measuring over time

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 researches is largely inaccurate and should not be relied upon for comparison.

The media often jumps to the findings of such surveys with enthusiasm. Websites that sell male enhancements often list findings of such exaggerated research to pressure potential buyers into buying their stock, which often is bogus or even harmful. The only two medically confirmed methods of increasing penis size are pumps and penis enlargement surgery.