This article is about penises and penis type condoms. While it was inspired by a big dick, this information is for penises of all shapes and sizes. 

One of my friends has a really big dick. Naturally, he is my go-to guy for all big dick related questions ie. “do you find it hard to buy pants?” (It was a serious question, that thing is girthy as hell.). On my last round of questioning, prompted by a booty call that rocked up to my house with a prized hog and no condoms, and then had the audacity to complain about having a sore dick from my “regulars”, my friend referred me to a website he had found helpful, The Big Dick Guide. “The ultimate guide for the well-endowed man.” Colour me intrigued. 

While I was obviously interested in reading about the struggles of well-endowed “men” (“men” because not all penis owners are men, not all men have penises), you know that the first article I actually clicked on was “Vagina Anatomy 101”. I don’t want to bash another blog but the line “the vagina is the interior part of the female sexual anatomy that is used in sex” made me legitimately spit out my coffee and exit the site.

Anyway... condom sizing… amiright?

So we know that condoms are important because they reduce the risk of pregnancy and the spread of STIs, but it turns out wearing the right size condom is also really important… for more than just being comfortable reasons…

If a condom is too small;

-       The integrity of the material can be compromised, and it may break.

-       The condom being too tight can cause discomfort or if left on for too long can start to cut off circulation – I assume this is what happened to old mate… yikes. 

If a condom is too big;

-       Semen can leak out of the sides.

-       It can slip off and get lost in your hole forever. Just kidding. About it getting lost that is. If it’s too big it can 100% slip off.

How are condoms sized?

I will save you the anecdotes of how I came to this conclusion, but I would recommend ignoring the buzzword on the front of the packaging and use the “nominal width” measurement (on the back or side of the box) instead. The nominal width is how wide the condom is when it’s rolled out and lying flat. How does that apply to a penis? I hear you asking…

~ Immediately indulges in anecdotes ~

Well, I nearly had mental breakdown trying to clue that one out pal. Just picture me sitting on the lounge room floor, surrounded by dildos, measuring tapes and unrolled condoms. Alternating between screaming “WHAT DO YOU MEAN?!” at my calculator and “C = p x D \ D = C ÷ p IS NOT WORKING” at the website that ensured me this equation was the key to converting penis size to nominal width…

It was the 8th google search that I found the answer. An article that clearly explained everything about condom sizing and nominal width and why the equation C = p x D \ D = C ÷ p doesn’t work… That article was on Big Dick Guide.com.

The author, Magnus Cox, gives the following very simple sum. To find the recommended nominal width of the penis, multiply the girth by 4.5. That’s in cm. If you’re using inches, multiply by 11.5. He then says to keep within 5mm above or below that number…

If you want to know how I reacted when this new equation worked for me, I’d say it was on par with someone who just found the image of jesus on their toast.

Finding the perfect fit

First up you need the girth measurement. Take the measurement at the widest / thickest part of the shaft when the penis is erect. Best practices call for a soft measuring tape but if you don’t have one / don’t want to raid the family sewing kit, you can use a thin strip of paper or a piece of string. Just mark the spot where the paper or string meets and then lay it out onto a ruler. My dildo, Big Red, is 15cm.

Next, using the calculation from Magnus, multiply that measurement by 4.5 and answer will automatically be in mm. If you’re using inches, multiply by 11.5 instead and then I don’t know what the answer comes out as... I don’t understand the lunacy that is the imperial system.

15cm x 4.5 = 67.5mm. There you have it. Big Red’s nominal width is 67.5mm.

Keeping within the 5mm on either side of that, as Mr Cox suggests, I now have a size range I can easily look out for when I go condom shopping.

If the condom doesn’t feel quite right or you’re still having a bit of trouble, it could be the design or shape of the condom. Try a condom with a flared tip to give the glans (head) more space. Remember, all of our bodies are different, and it might take a bit of trial and error to find the perfect fit.

Closing statements

If you’re reading this because someone in your life is using their penis size as an excuse to not wear condoms, that ain’t it hun. I hope you either use this info to find them condoms that fit, or use it as me pointing out the red flag that is them trying to manipulate you into unprotected sex.

Do yourself a favour and listen to the Search Engine Sex episode “How to measure a penis”. Listen to all of them but that one is particularly great.

Big Dick Guide – This seems like a good resource and there are clearly people out there who need it but if you’re going to check it out, I will let you know that from what I read it is very… heteronormative. By that I mean it seems like a site written by a straight cis man for an audience of straight cis men. This may not be an issue for you, but I just wanted to put it out there.