How to Determine Condom Size

Measuring the Girth of Your Penis

Wrap a measuring tape or string around the thickest part of your erect penis. This is the circumference of your penis. The thickness of your penis is what most influences your condom size, though the length of your penis can also affect the size you need. The girth is more important than the length because the condom will not adjust much to allow for a thicker or slimmer penis. However, the length can be flexible. A condom that is too long can be rolled down at the base, while a condom that doesn't reach the base of the penis still offers adequate protection if it correctly fits your girth.

Hold the tape or string where the end meets the loose portion. There shouldn't be any slack in the tape or string, but you also don't want it to be tight against your skin. Place your finger or make a mark at the point where the end of the tape or string meets the remaining portion. You may be tempted to add a little slack to increase your measurement, but remember that this opens you up to risk because your condom won't fit well. No one but you has to know your number, so be accurate.

Check the measurement. If you used a measuring tape, you could just check the number on the tape itself. If you used a string, lay the portion that you wrapped around your penis on a ruler to get the measurement. Write this number down or note it somewhere, such as in your phone. This is your girth measurement.

Measuring the Length of Your Penis

Place a ruler or measuring tape against the base of your erect penis. Move aside any hair that covers the base. Rest it firmly against your skin, but don't press down on it. While it's possible to find a condom that fits well without measuring the length of your penis, most condoms include the length of the condom on the box. Knowing your length will allow you to choose between brands.

Hold your penis flat against the ruler or tape. There should be no extra space between them. Gently hold your penis, and avoid pulling on it. If you have a curved penis, use a soft ruler or a measuring tape and push it against the curve to get the accurate length.

Note the measurement. Take your measurement to the nearest .25 inches (6.4 mm). Most condoms will include measurements that range in inches or centimeters, but it's good to know where you fall in that range. For example, if you are choosing between two lengths and your penis is 5.25 inches (13.3 cm), you may choose a condom that has a length measurement of 4 to 6 inches (10 to 15 cm) rather than one with a length of 5 to 7 inches (13 to 18 cm).

Finding a Condom That Fits

Look for a standard size if your girth is between 2 to 2.05 inches (5.1 to 5.2 cm). Standard sized condoms are the most prevalent, so you'll have many choices. You'll be able to find condoms that are basic, as well as some that have different textures, lubricants, or flavors. While they will be the same basic size, you may find that different brands fit a little differently. Although they will all be safe, you will want to look for one that is most comfortable for you. You can use the length measurement of your penis to choose a brand with a similar length.

Choose a small or snugger fit if your girth measures less than 2 inches (5.1 cm). Most small condoms are labeled as “snugger fit.” While there are fewer readily available options, you can find selections from several major brands at either a drugstore or online. When choosing between brands, don't forget that you can look on the box to find the length of the condom.

Try a larger size if your girth is greater than 2.05 inches (5.2 cm). These condoms are often labelled as “magnum” or “XL.” You will not find as many varieties as standard condoms, but they are easy to find in drugstores or online. If you are choosing between brands, remember to compare your length to the condom length listed on the box. Buying condoms that are too large is a common tendency among men. However, remember that you are exposing your partner and yourself to the consequences of unprotected sex if you are intentionally choosing condoms that are too big. Only buy large condoms if your girth is too thick for standard condoms, based on the measurement.

Make sure the condom leaves space at the tip for your ejaculate. This will reduce the likelihood that the fluids rise up the sides of the condom and leak out. Some condoms will taper near the end to create the space. Otherwise, make sure to leave a gap at the top when you put on the condom. It's okay to have extra length of condom rolled up at the base of your penis. If your girth requires a condom size that is longer than your length, just roll up the extra at the top until it fits.

Try a few different brands in your size to see which feels best for you. Even when you buy the right size, your comfort level as well as your partner's can vary depending on the type of condom you're wearing. It's a good idea to try different options to figure out which works best for you. Some condoms will fit tightly, while others may be tight near the base but loose over the top of the penis.