What Ethernet Cable Do I Need? How Do I Choose? Cat 5 to Cat 8 Compared

The highest speed Ethernet cable now available is known as Cat 8. And, yes, the type of Ethernet cable you use can significantly impact your online experience.

Not all Ethernet cables are created equal, and the one you're using could be holding your Internet speed back. Our guide compares Cat 5 through Cat 8 Ethernet cables side by side, breaking down max speed, bandwidth and best use for each so you can find the right fit for your setup. Whether you're on a basic plan or Optimum's 8 Gig Fiber Internet, learn which cable category matches your connection-and why upgrading your cable might matter as much as upgrading your plan.

Choosing the right Ethernet cable comes down to matching the cable to your Internet plan and your future needs. This guide breaks down every category from the outdated Cat 5 to the enterprise-grade Cat 8, comparing max speed, bandwidth and ideal use case for each. You'll learn why Cat 5e is the minimum for Optimum Fiber's 300 Mbps, 500 Mbps and 1 Gig plans, why Cat 6a is the sweet spot for multi-gig speeds, and when a short-run Cat 8 patch cord makes sense for power users on 8 Gig Fiber Internet. We also cover how Ethernet stacks up against Wi-Fi 7, and how to tell if your current cable is quietly capping the speeds you're paying for.

What is an Ethernet cable?

Ethernet is an Internet technology that facilitates the connection between different devices on a single network. An Ethernet cable is a physical, encased set of wires that connects to your modem or router as well as the device you're using (like your computer). Plugging this cable in allows data to travel directly between connected devices via a unique language known as a protocol.

Comparing Ethernet cable options

While all types of Ethernet cables work in more or less the same way, there are key differences between Ethernet cables that you should know before purchasing one. Ethernet cables are made up of twisted pairs of wires, typically insulated to reduce electromagnetic interference. If you have Optimum Fiber Internet, you’ll need at least a Cat 5e cable to support our 300 Mbps, 500 Mbps and 1 Gig plans. With our fastest service—8 Gig Fiber Internet—you’ll want a premium Cat 6a cable or a short-run Cat 8 patch cord.

Use the chart below to understand the speed, bandwidth and best uses for each type.

Cat 5 Cable

The most basic Ethernet cable is the Cat 5. This cable is very outdated and hard to find. The only households that should be using a Cat 5 are those with Internet plans with speeds lower than 100 Mbps. If you currently have a Cat 5 cable and need to replace it, however, we suggest upgrading to a Cat 5e, as it’ll still be useful if you decide to upgrade your Internet speed in the future.

Cat 5e Cable

A Cat 5e cable is the current standard. This standard Ethernet cable can support Internet plans with speeds up to 1,000 Mbps and helps get rid of unwanted transfer of signal between the cables, leading to a stronger connection. The estimated price for a 12-foot Cat 5e cable is less than $10, making it an affordable option for most households.

Cat 6 Cable

The Cat 6 cable offers support for the same speeds as the Cat 5e but will double your bandwidth. Having a higher bandwidth increases both download and upload speeds. Some Cat 6 cables also offer shielding to protect the wires inside your Ethernet cable from electromagnetic interference. If you want this feature, look for "STP'' or "shielded twisted pair" when looking for Cat 6 cables.

Cat 6a

Cat 6a cables increase speed and bandwidth when compared to the Cat 6 cable. In addition, all Cat 6a and higher cables guarantee shielding to eliminate electromagnetic interference entirely. A Cat 6a cable will support your high-speed Internet connection for years to come, even as faster cable and Fiber-optic Internet speeds become available.

Cat 7

One of the newest Ethernet cables available is the Cat 7 cable. While this is newer technology available on the market, the Cat 7 doesn't offer much more than the Cat 6a aside from higher bandwidth. Cat 7 cables support speeds of up to 10,000 Mbps, and 600 MHz of bandwidth, while Cat 6a supports 500 MHz. This higher bandwidth enables faster data transfers, so if you want to download or upload large files, the Cat 7 might be right for you.

Cat 7a

While you might see Cat 7 or Cat 7a cables heavily marketed online as a premium choice, they are generally not recommended for your home network.

Although they support speeds up to 10,000 Mbps with a 1,000 MHz bandwidth on paper, the Cat 7a standard is a non-standard framework that was completely bypassed by North American telecom standards bodies (TIA/EIA). It requires specialized, proprietary connectors to achieve its maximum performance, meaning it won't be easily compatible with mainstream upcoming home technologies. Instead of investing extra money in Category 7, home users looking to future-proof their network should stick with a standard Cat 6a cable or leap directly to Cat 8.

Cat 8

If you are looking for the absolute highest speed Ethernet cable available on the consumer market, Cat 8 is the reigning champion. It represents a massive technological leap, supporting blazing-fast data transfer speeds up to 40 Gbps and an ultra-high frequency bandwidth of 2,000 MHz.

Because it requires intensive layer-by-layer shielding to prevent signal distortion at those extreme speeds, the physical cable is built like a tank—making it notoriously thick, heavy, and very rigid to bend around tight household corners.

While it was specifically designed for short-distance, high-density switch connections inside commercial data centers, Cat 8 uses standard RJ45 connectors. This means it is fully backward compatible with your home devices. For a standard home network, a Cat 8 cord is massive overkill.

However, if you are a competitive gamer or power user looking to run a short, zero-compromise patch line directly from your high-performance PC to an Optimum 8 Gig Fiber Gateway, a short Cat 8 cable will ensure you never drop a single frame of data.

What does the Ethernet cable connect to?

The Ethernet cable connects to two devices: the hub (usually a router or modem) and your Internet-enabled device. Setting up an Ethernet connection is as easy as connecting the cable. Simply connect your Ethernet cable so that one end is plugged into your computer and the other is plugged into an Ethernet port on your hub (usually the router's Internet, Uplink, WAN or WLAN port). It’s also important to make sure that the port you connect the cable to is compatible—in other words, it’s capable of supporting the same speed as your chosen Ethernet cable.

Is Ethernet faster than Wi-Fi?

Your Internet speeds depend on several factors, including the plan you choose and the capability of your devices. As such, using an Ethernet cable may be faster than WiFi in some cases, but not always. However, there are other benefits of Ethernet cables worth considering.

Using an Ethernet cable allows for rapid data transfer, especially if you have a Fiber-optic Internet connection. Another perk of an Ethernet connection is that router placement doesn't matter: As long as your cable reaches your devices, you won't have to worry about slow speeds. Your data is less likely to get lost or degrade as it’s transferring, and you won’t have to worry about the signal being blocked by nearby barriers.

In fact, the only way a disruption can occur is if your Ethernet cable physically breaks. Lastly, an Ethernet connection can't be hacked by unauthorized users. To utilize the connection, your device must be physically connected to the cable.

What is the fastest alternative to Ethernet?

Historically, hardwired Ethernet connections were considered the only way to experience true gigabit speeds. However, with the rollout of Wi-Fi 7, natively supported by Optimum, wireless networking has drastically closed the gap. This latest iteration of Wi-Fi provides massive multi-gigabit wireless throughput, easily outperforming standard 1 Gig legacy Ethernet connections.

Premium high-speed internet tiers from Optimum include Smart Wi-Fi capabilities. The next-generation Optimum Gateway is at the heart of it all, engineered specifically for users who want to maximize the elite multi-gigabit speeds they pay for. You'll stay seamlessly connected on one powerful mesh network without sacrificing mobility.

For larger floor plans or multi-story homes, Optimum Xtend is available. It's an advanced Wi-Fi extender that integrates perfectly with your Optimum Gateway to ensure complete wireless coverage, even in the most difficult-to-reach areas of your home.

Ultimately, you have many options when it comes to connecting your devices. But whatever your setup requires, Optimum has a wireless or wired solution to fit your needs. Are you getting everything you need from your home Internet? Explore all of Optimum's Internet plans.

Frequently Asked Questions (FAQs)

What is the fastest Ethernet cable you can buy right now?

Cat 8 is the fastest Ethernet cable available; Cat 8 supports up to 40 Gbps over short distances (typically 30 feet or less) and up to 2,000 MHz of bandwidth. This cable is ideal for data centers versus in the home; however, if you may consider a Cat 8 if you're using Optimum's 8 Gig Fiber plan between a modem and a single nearby device.

Do you need a Cat 8 Ethernet cable for a home network?

No, a Cat 8 is typically used by data centers. These cords are rigid, which means they aren't easy to install and aren't ideal for home use.

Will a faster Ethernet cable increase my Internet speed?

Your Ethernet cable will only improve your Internet speed up to the capabilities of your plan. However, your cable can slow down your connectivity. For example, if you use a Cat 5e cable on Optimum Fiber Internet plans of 1 Gig or higher, your connection will feel sluggish.

Is Ethernet faster than Wi-Fi?

Yes, particularly for multi-gig speeds. While Wi-Fi 7 is incredibly fast, a hardwired Cat 6a connection is the only way to reliably lock in the full 8 Gbps of a multi-gig fiber plan without wireless drop-off.