Why we may need an RJ45 coupler?

Copper Cables are widely used to connect many devices. Some of the more popular ones would have to be smart TVs, gaming consoles, modems, and computers. We also need to include things like access points, media converters, and lots of other devices to this list as well. Most likely you will find that these devices are not located in one spot.

Many older homes or offices did not anticipate the need for all these extra devices and did not allow enough access points in the building.

And sometimes because of this, you need to extend your existing Ethernet cable. Needing longer lengths of copper patch cables is therefore not unusual. 

Obviously, you would always opt to buy the correct length, that suits your application. But if this isn't possible, for some reason, then you could try attaching an RJ45 inline coupler to extend the length of your cable run.

You may already have a significant amount of cable installed in the wall of your building to access points already there, only needing to relocate a short length further than where you are, and could consider using an RJ45 coupler in this instance.

What is an RJ45 coupler?

A registered jack-45 (RJ45) coupler is a device with two female RJ45 jacks enclosed in one casing. Usually, this casing is made from either plastic or metal.

An RJ45 Coupler connects to one end of a male RJ45 copper cable and allows the same type of cable to be plugged into the other side, continuing the connection between these two cables. This ensures an easy way to "lengthen" an already existing cable run.

They are small, inexpensive, and can easily fit into the palm of your hand. They also come in a range of colours to suit your applications or just to brighten up your workplace or play area. Definitely, something handy to have ready and available.

What does an inline coupler do?

Within the coupler is a marvel of technology, ensuring that as many as eight connections on each side are precision aligned and they are fitted so tightly that signals will pass through them without any or minimal loss of signal integrity or delay.

The inline coupler comes with a notch on either side that fits the flexible tab on the RJ45 connector to secure the Ethernet cable firmly and prevent its incorrect insertion. You complete the coupling by inserting the second Ethernet cable into the other side.

Will a Cat6 coupler work with Cat5?

The short answer is “Yes”,

The RJ45 plug is standard and most likely will only have a different coating on the pins to make it Cat6 compatible vs. Cat5.

However, you should always try to match couplers to the network wiring.

For example, not all Cat6 cables will deliver optimal signal quality when connected through a Cat5 coupler; it would be better to purchase a Cat6 coupler in that case. But you could use a CAT6 coupler for CAT5 cables with no issues.

Does an RJ45 coupler reduce speed?

RJ45 Couplers are designed such that the speed is maintained.

You should, therefore, not experience any degrading or lower speeds of your network's signal by using an RJ45 inline coupler.

There could be other issues though;

  • -        Cable length is too long to operate correctly.
  • -        User error – not plugged in correctly/firmly.
  • -        Poor or incorrect termination of the connector.
  • -        Damaged Cable.
  • -        Bad or cheap quality coupler.


Having a wired network that is too short causes issues. Using an RJ45 coupler can be an easy solution to this problem.

Just remember, the more superior the quality of the couplers and cables you are using, the more reliable and durable the connection will be.