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How to Measure Penis Size


Updated April 01, 2014

How to Measure Penis Size

How to Measure Penis Size

Photo © 2011 Dawn Stacey

When it comes to choosing the perfect condom for you, there are a few steps you may need to take. First, you may do some experimenting with different condom materials (like, latex, polyurethane, polyisoprene, and lambskin) as well as play around with various textures and lubricants.

Yet perhaps even more important in your quest to find the perfect condom is to measure your penis size. Condoms that are too big can slip off and ones that are too tight can break -- neither scenario is one you want to be in. The following will guide you through the simple steps on how to measure your penis size.

Difficulty: Easy
Time Required: 15 minutes (after you have an erect penis)

Here's How:

  1. In order to accurately measure penis size, first you must have an erect penis (since penis size when flaccid is not an accurate measurement). How you choose to accomplish this task is up to you. But we can’t move any further in determining penis size until your penis has assumed the proper position!

  2. Measure Penis Length -– Start off by measuring the length of your penis. All you need to do is use a ruler or measuring tape. Position the ruler or measuring tape at the base of your penis (where it attaches to your body –- make sure to press into the pubic bone as far as you can because fat can actually hide the length of your penis). Measure your penis length by marking how long it is from the base all the way to the end of the tip. Write down this number and label it “penis length”.

  3. Measure Penis Girth -– Now you will be measuring around your penis, basically figuring out its circumference/thickness, or penis girth. For this step, you need to use a piece of string (or something similar) or a soft measuring tape. Gently wrap the string one time around the thickest part of the shaft/body of your erect penis (yes, it still needs to be erect!). Mark where the string meets and then measure the distance of the string with a ruler. You could also do the same thing with the soft measuring tape, and just mark the measurement once you reach around the penis. Write down this number and label it “penis girth”.

    You can determine penis width or diameter by dividing the girth measurement by 3.14.

  4. Great! Now you have a good idea of your penis size, and it’s time for the fun part (an erect penis is no longer needed). It is time to compare your penis size with the average penis size. Typically, the average erection has a penis length of approximately 5.5 to 6.3 inches (139.7 to 160.02 mm) and has a girth ranging between 4.5 to 5.1 inches (114.3 to 129.54 mm). The average diameter (penis width) would equal out to about 1.4 to 1.6 inches (35.56 to 40.64 mm). If your penis measurements are close to these averages, then a standard size condom should provide you with the most accurate fit. Keep in mind that a condom should completely cover your penis and have some space at the tip to catch the ejaculate.


  1. It may be best to use condom width when comparing condom sizes. As a general guide, condoms with a width of 1.75 to 2 inches (44.45 to 50.8 mm) are typically considered standard, while those under 1.75 inches are categorized as snug and condoms over 2 inches are considered large.

    Going by length may be confusing because different condom manufactures use slightly different measurements, so what one manufacturer calls large may actually be standard for another. Because of this, standard condoms may have a length between 7.25 to 7.8 inches (184.15 to 198.12 mm); snug condoms may have a length of 7 to 7.8 (177.8 to 198.12 mm); large condoms length ranges from 7.25 to 8.1 inches (184.15 to 205.74 mm).

  2. Keep in mind that penis girth affects how a condom fits. If your girth is above average, a standard sized condom might feel too tight, and if penis girth is less than average, standard condoms may slip off during sex.

  3. A non-erect penis measurement is rather valueless since many factors can cause a temporary penis shrinkage of two or more inches (like cold weather or going swimming).

  4. To get the most accurate measurement of penis size, you should repeat the above steps 1-3 at different times throughout the day over several days. Penis size can vary due to stress, fatigue, frequency of sexual activity and arousal levels.

What You Need

  • Ruler
  • Soft Measuring Tape or String
  • Pencil/Pen
  • Paper
  • An Erect Penis!

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