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How to choose an Ethernet cable

Figuring out which Ethernet cables will work best for you without going overboard is hard, but we’re here to help. We’ve put together a helpful guide that includes a table, glossary, and other buying tips that compare the benefits and issues of different Ethernet cables. Our explainer below is a great way to start figuring out how to choose the best Ethernet cable for your home or work environment.

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Ethernet cable types

Category Shielding Max Transmission Speeds  Max Bandwidth
Cat 3 Unshielded 10Mbps 16MHz
Cat 5 Unshielded 10-100Mbps 100MHz
Cat 5e Unshielded 1,000Mbps to 1Gbps 100MHz
Cat 6 Shielded or unshielded 10Gbps up to 55 meters 250MHz
Cat 6a Shielded 10Gbps up to 55 meters 500MHz
Cat 7 Shielded 100Gbps up to 15 meters 600MHz
Cat 7a Shielded 100Gbps up to 15 meters 1,000MHz
Cat 8 Shielded 40Gbps up to 30 meters 2,000MHz

The easiest way to select a cable is to pick one with the range and performance you need.

But what do you need?

Start with the speed of your home internet connection. If you have gigabit internet (1Gbps), an old Ethernet cord will hold you back. If you have a slower connection — perhaps 10 or 20 megabits per second — you’re good with anything Cat 5 or newer.

If you don’t know your internet subscription’s actual speed, connect your PC directly to the modem and load this speed test. Doing so will give you a starting idea of what you’ll need in terms of wired connectivity. If your subscription only supports 50Mbps downloads, purchasing a 1Gbps Ethernet cable is simply overkill — at least for now.

Next, consider the speed needed for your network. This knowledge is irrelevant to most home users. Still, if you frequently move big files between computers or stream extremely high-bandwidth video, a better Ethernet cable can make a huge difference. If that’s not the case and you only surf the internet’s shallow waters, you don’t need a fast in-home network.

As today’s routers become faster and more capable, facilitating faster network speeds, you need more capable cables to take full advantage. If you are looking for a replacement cable, it’s a good idea to choose one of the more recent versions to both take advantage of speeds and future-proof your setup for years to come. That usually means picking a Cat 6a or even a Cat 8 cable. On its own, a fast Ethernet cable won’t make a big difference, but a good cable can work together with other high-end network devices to ensure that your connection is as strong as possible.

Which is the best Ethernet cable for you?

Close up of a person's fingers on a laptop's keyboard which has a Ethernet cable plugged into it and there's a smartphone next to the laptop.

When shopping for cables, you may notice they’re nearly always classified as “Cat-5,” “Cat6e,” or something similar. “Cat” simply stands for “Category.” The number that follows indicates the specification version supported by the cable. A general rule of thumb is that higher numbers represent faster speeds and higher frequencies, measured in megahertz (MHz). As is the case with most technologies, newer cables typically support higher bandwidths and therefore increased download speeds and faster connections.

Keep in mind, though, that longer Ethernet cables have slower transmission speeds. This is why Ethernet cables tend to have two speed ratings, one at 10 to 30 meters and one at 100 meters. Since the 100-meter rating doesn’t matter outside of very large professional projects, we suggest just focusing on the 10- to 30-meter numbers.

Below, you can see the capabilities of each cable type.

(We’re skipping categories 1, 2, and 4, as they are not technically recognized as Ethernet standards and have no application today. We’re also skipping 3 and 5 because they are obsolete, slow, and discontinued.)

Cat 5e

The “e” in Cat 5e stands for “enhanced.” There are no physical differences between Cat 5 and Cat 5e cables. However, manufacturers build Cat 5e cables under more stringent testing standards to eliminate unwanted signal transfers between communication channels (crosstalk). Cat 5e is currently the most commonly used cable, mainly due to its low production cost and support for speeds faster than Cat 5 cables.

Cat 6

The Cat 6 Ethernet cable supports higher bandwidths than Cat 5 and Cat 5e cables. They’re tightly wound and usually outfitted with foil or braided shielding. Said shielding protects the twisted pairs of wires inside the Ethernet cable, which helps prevent crosstalk and noise interference. Cat 6 cables technically support speeds up to 10Gbps for up to 55 meters. That speed comes with a price, however, as a Cat 6 cable is more expensive than Cat 5 and Cat 5e variants.

Cat 6a

The “a” in Cat 6a stands for “augmented.” Cables based on this standard are a step up from Cat 6 versions by supporting twice the maximum bandwidth. They’re also capable of maintaining higher transmission speeds over longer cable lengths. Cat 6a cables come shielded, and the sheathing — which is thick enough to eliminate crosstalk — makes for a much denser, less flexible cable than Cat 6.

Cat 7 and Cat 7a

Cat 7 and Cat 7a cables are high-performing but tend to be useless for most people. Let’s get into why:

Cat 7 cables support higher bandwidths and significantly faster transmission speeds than Cat 6 cables by utilizing the newest widely available Ethernet technology. Cat 7 cables reach up to 100Gbps at a range of 15 meters, making them one of the most capable categories of Ethernet cables. Cat 7 cables always are shielded, and they use a modified GigaGate45 connector, which is backward compatible with RJ45 Ethernet ports.

That modified GG45 connector is a proprietary component, though, and while the backward compatibility helped a little, there are still issues with following previous Ethernet standards. This led to most manufacturers avoiding the Cat 7 standard, which is why it’s quite rare today. That difficulty led to the development of Cat 6a — and a lot of marketing confusion since some sellers started referring to Cat 6a as the new Cat 7. Always check the specs before you buy — and when in doubt, we suggest just going for Cat 8 instead.

Cat 7a offers one of the highest-specification Ethernet cables you can buy, but it’s not widely available and offers only a few supporting networking hardware options. The 7a standard was designed to support 40 Gigabit Ethernet connections up to 50 meters and — just like Cat 7, but with improvement to the overall bandwidth — more than 50%. This improvement may be useful in some instances, but Cat 7a cables are far more expensive than any other option. Consider using Cat 7a only in very niche cases.

Cat 8

Although these cables are currently available for purchase, you may find that they’re excessive and overkill for just regular home use. This standard promises a maximum frequency of 2,000MHz and speeds of up to 40Gbps at 30 meters. That high frequency also requires shielding, meaning you’ll never find unshielded Cat 8 cables. Even more, Cat 8 supports two connectors. Thus it only allows for three connected cables with a combined length of 30 meters. Cat 8 cables will cost more than other options, but they have become more affordable these days. You can find options for a 10-foot Cat 8 cable under $15.

Cat 8 also is the only cable to meet the latest IEEE standards (the aforementioned 40Gbps and 2,000MHz frequency), which is one reason it’s a great choice for future-proofing, despite the significantly higher costs. As an added bonus, it also skips the connector mess of Cat 7.

Ethernet cables glossary

Close up of four Ethernet cables plugged into their ports: two yellow cables and two blue ones.

It’s easy to distinguish between the Ethernet cables out there today. However, it’s also easy to get confused by the complex terminology associated with these products. We want to help you out. That’s why we’ve outlined a few standard Ethernet-related terms and explained what each word means while also giving you a solid idea of what you can expect when you purchase each type of cable. 

Types of cables

Cat: This term is the short version of “category.”

TP (Twisted Pairs): These types of Ethernet cables consist of wires that twist together inside. Twisted Pairs are prevalent in the industry. These kinds are secondary only to fiber-optic cables regarding their max length and amount of speed deceleration.

UTP (Unshielded Twisted Pairs): Unshielded Twisted Pairs don’t feature any foil or an intertwined protective covering. This type of design allows them to be increasingly flexible and much more inexpensive to manufacture. However, it’s important to note that a UTP cable may lack good signal quality and pose an increased risk for crosstalk. 

STP or SSTP (Shielded Twisted Pairs): These specific Ethernet cables are protected by robust and braided shielding. The covering on an STP cable is typically made of copper or another type of conductive substance and aids in noise reduction and enhancing connection quality.

FTP or SFTP (Foiled Twisted Pairs): Foiled Twisted Pairs are another type of Ethernet cable that features a foil shield to secure the wires. Many people use these particular cables to reduce noise, boost connectivity, and achieve a better connection.

Ethernet connectors

Ethernet connectors use a specialized design with eight pins that must lock into place, typically called an 8P8C connector. Ethernet cables have a couple of different types of 8P8C connectors, and knowing the difference will help you understand different Ethernet categories more clearly:

RJ45: This is the standard “Registered Jack 45” connector that Ethernet cables use. There are two variations based on how wires are colored and arranged, the more popular T568B standard and less common T568A standard (not particularly important unless you are doing detailed wiring). The RJ45 connector is used on nearly every Ethernet category, from Cat 1 to Cat 6 as well as Cat 8.

GG45: For Ethernet Cat 7 cables, standards briefly switched to a new connector called GigaGate45, or GG45. GG45 came with several additional conductors for some frequency versatility. It is backward compatible with RJ45 connectors, but the new connector was deemed largely unnecessary, which is why Cat 8 switched to RJ45.

EtherCON RJ45: RJ45 connectors are easy to use but not always durable — their built-in plastic clips can break, among other issues. EtherCON is a ruggedized version of the RJ45 connector made by Neutrik and used in situations where the traditional RJ45 connector is too fragile, often with professional A/V work.

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