Cat5 cable is a standard term for twisted pair cable commonly used for connecting PCs and hardware to different equipment. It has been replaced by Cat5e, which is an enhanced version of Cat5. These share many of the same physical characteristics including distance limitations, but Cat5e is designed for faster networking speeds and reduced crosstalk interference. The maximum length you can run Cat5, Cat5e, Cat6 and Cat6a cable is 100 meters or 328 feet. If you require a longer run, you will need to put an active component, such as a router, in-between the signals.

The length limit for Cat5 also includes any patch cables, jacks or couplers that are connected in the run. For example, you could not run 100 meters of Cat5 cable between the walls, and then connect with a jack to another 10 meter cable. In terms of distance limitation, the 100 meters of Cat5, the jack and additional 10 

meters of Cat5 are all seen as a single length of cable. It is recommended to only run the structured cabling (the horizontal cabling or the infrastructure cabling) 90 meters to give adequate length for end users patching into the network jacks.

Although Cat5 has been eclipsed by Cat5e and now Cat6 cables, the Cat5e and Cat6 max length distance limitation remains unchanged. If you need to go farther than 100 meters and can’t add an active component, you will need to use fiber optic cable. Depending upon the type of fiber you use, the distance limitation can be up to 10 kilometers. By using a fiber media converter, you can integrate fiber optic cable into your copper (cat5, cat5e, cat6) network.