What Is the Minimum and Maximum Ethernet Cable Length

Are you working on a project where you have to use a considerable amount of Ethernet cable? If so, you’re probably wondering how much cable you can use and still count on your system working correctly. 

You may even wonder if there’s a minimum amount you can use. Fortunately, there are some tried-and-true industry standards to share with you regarding minimum and maximum Ethernet cable lengths, so you’ll be able to tackle your project confidently.

What is the Maximum Ethernet Cable Length?

The popular CAT5e, 6, and 6a cables share a maximum length of 328 feet or 100 meters. That means you shouldn't use more than 328 feet of cable to connect any two powered devices, such as a network switch and a computer.

For example, suppose you wanted to run a patch cable from a router on the first floor of your home to a computer in the basement. Using CAT5e cable, you would have 328 feet to work with without encountering any problems.

Another way you might solve the problem is by installing a permanent link within the structure of your house. Installers lay a permanent link behind walls and end the links with wall jacks. So you could have wall jacks in several of your rooms, including the basement. 

However, the principle regarding the Ethernet cable length limit from one powered device to another would still apply. A permanent link is allowed to be 295 feet. That leaves another 33 feet of patch cable that you could plug into either end of the permanent link and connect your devices.

So, upstairs, you could use 16.5 feet of patch cable connecting your router to a wall jack. Then, you could use 16.5 feet of patch cable in the basement to connect your computer to the wall jacket downstairs.

But your overall length shouldn’t extend past 328 feet from the upstairs router to the downstairs computer. Of course, in the typical home, it’s unlikely that you will need to get even remotely close to the max Ethernet cable length, but the illustration gives you an example of what’s possible.

Important rule to remember: For best results stay consistent with the category of cable you use. Don't mix categories in one run. For example, if the permanent link between your wall jacks is CAT5e, you should also use CAT5e patch cables to connect your router and computer to the wall jacks.

How Far Can You Run Ethernet Cable outdoor?

328ft / 100m, it doesn't matter whether you run Ethernet cables indoor or outdoor the same principal will apply. Just make sure to use Outdoor rated cables for outside applications.

Does Each Category of Ethernet Cable Have a Different Cable Distance Limit?

Each time there’s an improvement in Ethernet cable technology, the new cable receives a higher number-letter combination than its predecessor. But the larger number doesn’t necessarily reflect an increase in the maximum length of Ethernet cable.

CAT5e, 6 transmit data at a speed of 1 Gbps for 328 feet. But if you use a CAT6 cable of only 180 feet or less, you can see speeds of 10 Gbps.

CategoryMax Channel LengthMax Speed
Cat5e328ft1Gbps
Cat6180ft / 328ft10Gbps / 1Gbps
Cat6A328ft10Gbps
Cat7328ft10Gbps
Cat898ft / 328ft40Gbps / 25Gbps

Why is There a Limit and What Happens if the Cable is Too Long?

Electrical signals traveling through wires degrade with great distances. The farther they go, the more degradation you can expect until the signal is no longer usable. Either the cable will fail to deliver the signal to its target location, or the data will be corrupted beyond use.

The maximum recommended length of a cable is the distance between powered devices that you can reliably expect the cable to perform according to its design. For example, a CAT5e cable should pass data safely for 328 feet at a speed of 1 Gbps. But once you lay a cable that surpasses the maximum recommended length, the data rate is no longer predictable.

Do Longer Cables Reduce Speed?

No, not unless you try to use a length of cable greater than is recommended. A signal speed drops once the cable goes beyond its recommended limit. For example, CAT6 cable has a top speed of 10 Gbps for runs up to 180ft. Cat5e has a speed of only 1 Gbps. 

But if you were to run both cables for 328 feet or 100 meters, their speeds would be identical at only 1Gbps. Why? CAT6 cable can stay at top speed of 10Gbps for only 180 feet.

The maximum recommended length of a cable is based upon the assumption that the cable will operate under typical conditions. If the conditions are harsh, you can't expect the cable to achieve its top transmission speed over the usual maximum distance.

What are some factors that can shorten a cable's effective operating length? They include electromagnetic interference. If you need to lay cable where EMI presents a serious threat, choose shielded cable for extra protection.

Can You Extend the Length of a Cable?

If your application requires a longer cable than is standard, you’ll have to boost the signal to make sure it reaches its destination. Imagine a small child at one end of a long hallway using all his strength to push a toy car to the other end. But he’s too small and the hallway too long. 

The toy only makes it halfway before stopping. The kid has to give the car another push to get it to the end. He has to repeat his action.

Similarly, you can use a network switch to extend the distance your signal travels. Connect your first device to the switch using no more than 328 feet of cable. Then run another cable from the switch to your second device. Once again, make sure the cable length isn't longer than 328 feet.

Is There a Minimum Length for Ethernet Cables?

Manufacturers will generally limit their inventory to the most popular sizes for professionals and home users. However, if you need an ultra-short patch cable, you can make your own by attaching RJ45 connections to your desired cable length.

Professionals often do this to make their server racks neater. So, your cable can be as short as you want.

Have You Decided on Your Cable Length?

What length of cable do you need for your project? We carry Ethernet cables in several lengths to accommodate a variety of needs. Lengths start as small as 0.5 feet.

We also have connectors for you if you want to create customized cables of extraordinary lengths. Maybe your project requires the maximum Ethernet cable length. Or perhaps, you want an extremely short cable.

Either way, we're ready to help. Reach out with any questions by contacting SatMaximum team.