Figuring Out French Sizes: Urinary Catheter Sizes

urinary intermittent catheter french sizes blog header

Determining the right size of intermittent catheter to use can greatly increase the efficiency and comfort of your self-catheterization routine. But how does one choose the correct size to fit their individual needs? Read on to find out more!

Catheter Sizing: French Sizes

All internal catheters, including Foleys and intermittent styles, are sized by a universal gauge system which is referred to as a “French size.” This is based upon the measure of the external diameter of the tube.

The way the size is determined is a simple multiplication of 3 (diameters in millimeters multiplied by 3 = the French size). So, if a catheter has a diameter of 4.7 millimeters, the French (Fr) size is 14.

Catheter Funnel Colors

Most vinyl and silicone intermittent catheters with funnels use a universal color-coding system to help you determine what French size a catheter is. See the below chart for the most common French sizes along with their corresponding funnel color codes.

Catheter funnel colors

Wondering if you’re using the right catheter? Let us help. Click here to get your question answered by one of our catheter specialists.


Getting the Right French Size of Catheter

Why is determining the French size such an important part of selecting the right catheter for your needs? Efficiency and comfort are both important elements in the self-catheterization process. If you use a urinary catheter with too large of a diameter for your urethra, cathing can be more difficult and even painful. If it’s far too large, you will not be able to insert it at all.

Catheter Supplies

On the other hand, if you use a French size that is too small, you may find that the overall pace of draining your bladder will go much slower. On top of that, if you use a catheter smaller than your urethra, urine released from the bladder will not only escape through the catheter tube but could also go around it, which can get pretty messy, as the flow will be harder to control.

Luckily, there is a wide range of sizes all the way from pediatric sizes (for children) to larger French sizes, typically for adults. That way, you and your doctor can select the right size for you!

Catheters by French Size

Click on the links below to see all of the various catheters available in each catheter size:

Catheter Length

There are also varying lengths to accommodate for the different urethral lengths between genders and ages:

  • Pediatric  catheters are typically around 10 inches long
  • Female catheters range 6-8 inches in length
  • Male/Unisex catheters are usually 16 inches long

How Do You Find the Catheter That’s Right for You?

To determine the right size of the catheter for your individual needs, please be sure to consult with your prescribing healthcare professional, so that you can get a hassle-free experience with your intermittent catheters every time.

Contact 180 Medical on Live Chat or at 1-877-688-2729 to speak to one of our specialists. We are happy to find the right catheter for your needs. We can also verify your insurance for you to determine your catheter coverage.

Call Toll-Free (877) 688-2729

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About the Author
Jessica is the Senior Marketing Specialist at 180 Medical. She's been a part of the 180 family for over 11 years. Her favorite parts of working at 180 Medical are our values of compassion and integrity and the positive impact we help make on peoples' lives.

She loves writing, creating art, cooking, gardening, and spending time with her fiancé and their 3 dogs.