How to make your own Ethernet cable

Whether you want to make some cabling of a specific length or just wish to have a little more fun than picking up Ethernet cables from your local store, it's actually an easy and straightforward task to make your own. This process can also help you repair damaged cable in the home or at the office without having to fork out cash for replacements. To get started, here's what you'll need:

  • Ethernet cable.
  • Crimping tool.
  • RJ45 modular connector.
  • Cable tester.

For the cabling itself, you can pick up pre-assembled cabling that are ready to use and then cut to size or you could save some more money and pop to your local DIY store who should be able to cut some from a reel for you. You can pick up the crimping tool, modular connectors, and a cable tester in one package:

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The cable testing equipment isn't required (you can easily check by connecting the cable to your PC and router), but it makes things easier because you can just reach for a nearby tool and not have to fetch a device.

  1. Cut the cable to the length you require.

Ethernet Cable

  1. Using the crimping tool, strip away the cable jacket.
  2. Check to see if you nipped away at the wires inside.
  3. Spread the twisted wires out.(The thin thread that joins the four twisted wires allows you to pull the jacket back further, but note that there may be a plastic spine in the middle that requires cutting, along with the wires.)

Ethernet Cable

  1. Straighten out the wires.

Ethernet Cable

  1. Line them up in order, using the guides below:Looking at the underside of a connector, the copper contacts are in eight individual slots, numbered one through eight. We're using the T568B standard, which differs slightly from the T568A standard for wiring Ethernet cables.


  1. Slide the wires carefully into the RJ45 connector.

Ethernet Cable

  1. Insert the cable into the crimper tool and press hard to secure the connector.

The clamp within the connector should press against the cable jacket. You should now be able to test the cable using the tool or plug each end into a device and see if a connection is made.

Fear not if you don't get the wires lined up perfectly because it can take some practice to get the hang of preventing the wires from overlapping or locking as pairs into the connector. If you make a mistake, simply cut a bit behind from where you were working, and try again.

Rich Edmonds
  • Not bad, still need some technique to insert the cable into the RJ 45 jack
  • Just need RJ45-EZ's and appropriate crimper. Much easier. Sent from the iMore App
  • Yes, the other trick that is kind of mentioned, but maybe not clearly enough, is clipping off the wires to the right length so that they make it to the end of the connector, but that the jacket also goes in as far as possible so the crimp of the back-body of the connector gets the jacket.
  • "not" in the next-to-last paragraph should probably be "now.' Unless you need a lot of eithernet cables or cables of unusual lengths, they are not that expensive to purchase outright, but if you're a DIYer, this is a simple task.
  • Or just go to MonoPrice and buy one for a fraction of the cost of the equipment.
  • The upfront cost of buying tools, cable, and connectors is higher. However the amount of cables you can then make with said supplies drastically reduces the price point of each cable. Not to mention when making your own you can make specific lengths of cable for your needs to make wire management less of an issue and be more pleasing to the eye.
  • If your time isn't worth much, this makes sense. Otherwise, these cables are cheap as crap!
  • Sure, have unshielded, low quality cables running around your office in close proximity to other power cables and sources, surely that will not give any problems!
  • About 90% of patch cables are unshielded. The only STP cables are needed over UTP is if they are going to be run through areas where there is a lot of electrical interference. If they are passing near large motors or breaker panels, then yes, go for the STP. Othewise the UTPs are fine.
  • True, but I do both. If you can crank these things out, it still will take you about 2 minutes each. I just ordered fifty 12-inch cables from Monoprice at about $0.66 each for our patch panel to clean it up. At a cheap billing rate for consulting IT work, it's just not worth your employer's time to pay you $50/hr. 30 cables per hour would be almost 1.5 hours of work. That's almost double the cost to sit there and make cables. When it comes to that one-off time you need a longer or shorter or specific length of cable, yes. By all means, create a custom one. But not fifty.
  • I used to make hundreds (actually thousands) of them, but I agree with many of the others here... unless you need them for special application, you're probably better to just buy them (Monoprice ones are excellent quality and price). I used to have a tool that cost over $100 (back in the early 90s), if memory serves, and it made pretty reliable, durable cables. It got stolen and since I've used (when I rarely make one) a $20ish tool, and the results aren't nearly as good. It's certainly not a bad skill to have or know though, and great for a quick repair, etc. Edit: in case anyone is curious, it was something along the lines of this: What you're looking for, ideally, is a ratchet type, straight down pressure, rather than a simple lever. Like this one, the one I used had dies that could be swapped to do RJ-45, RJ-11, etc.
  • LOL "Slide the wires carefully into the RJ45 connector" like its just that easy. If you have to make your own cable either use RJ45-EZ plugs or its much much easier to terminate to a punch down jack.
  • Right on, brother. Platinum Tools EZ-RJ45 connectors are God’s gift to installers. The wires pass through the connector and are cut off by the specialized crimping tool. You will always have the wires inserted correctly because you can easily see them when they stick out the end of the connector. You can also get the twists as close to the termination point as possible (for CAT6 certification).
  • 7. Slide the wires carefully into the RJ45 connector. Sounds so simple. Not. It takes skill and practice to get those wires into the connector correctly and have enough jacket in to get a good crimp. Be sure to match the connector with the cable. Connectors for CAT5e are different from CAT6 connectors. CAT6 cable has thicker copper conductors (23 AWG) while CAT5e uses smaller conductors (24AWG). And now we have CAT6a cable and connectors for 10gig certification. If you are going to wire your house you also need to be aware of fire retardant code requirements. CMR cable is ‘riser’ cable for in wall applications. CMP is ‘plenum’ cable for when you run through ductwork. Then there’s the cost of the cable. The cheap stuff is usually CCA (copper clad aluminum) and not pure copper conductors. Solid conductors for house wiring, stranded conductors for patch cords and cables running from the jack to the desktop. There’s a whole lot of things to know if you’re going to do it right.