Ethernet gives you a direct, stable connection to your router

An ethernet cable is a physical wire that connects your computer directly to your router or modem. Unlike Wi-Fi, which broadcasts a signal through the air, ethernet sends data through a cable, which means faster speeds, lower latency, and a connection that does not drop when you move rooms or when other devices compete for bandwidth.

The cable itself is inexpensive — usually between $5 and $20 depending on length — and the connection process takes under a minute. You plug one end into your computer and the other into your router, and in most cases your computer recognizes the connection automatically.

Key Takeaways

  • Ethernet cables plug into a port on your computer called an RJ45 jack, which looks like a wider phone jack, and into a matching port on your router.
  • Most computers recognize an ethernet connection when ready and begin using it without any setup steps or driver installation.
  • Ethernet cables come in different lengths and categories; Cat5e and Cat6 are standard for home use and cost roughly the same.
  • If your computer has no ethernet port, you can add one using a USB adapter, which costs $15 to $40 and works with both Windows and Mac machines.

What you need before you start

You need three things: an ethernet cable, a computer with an ethernet port (or a USB adapter if your computer does not have one), and a router or modem with an available ethernet port.

Most desktop computers and many laptops have an ethernet port built in. It is a rectangular jack slightly wider than a phone jack, usually on the back or side of the machine. If you do not see one, your computer likely does not have one — this is common on newer MacBooks and ultraportable laptops.

Your router or modem also has ethernet ports, usually on the back. Most routers have four or more. Pick any port that is not already in use.

The physical connection: plug and wait

Take one end of the ethernet cable and push it firmly into the ethernet port on your computer until you hear or feel a click. The connector has a small plastic tab that locks into place. Do the same with the other end of the cable into an available port on your router.

Within a few seconds, your computer should recognize the connection. On Windows, you will see a notification in the system tray (bottom right of the screen) saying "Ethernet" or "Connected". On Mac, the ethernet icon appears in the menu bar at the top right, and the status will show "Connected".

That is the entire process. Your computer is now online through ethernet. You do not need to install drivers, enter a password, or run any setup software.

Choosing the right cable length and type

Ethernet cables come in standard lengths: 3 feet, 5 feet, 10 feet, 25 feet, 50 feet, and longer. Measure the distance from your computer to your router and buy a cable that reaches comfortably without being pulled tight. A cable that is too short will strain the connection; one that is too long will clutter your space.

You will also see cables labeled Cat5e, Cat6, Cat6a, and Cat7. For home use, Cat5e and Cat6 are both fine and cost about the same. Cat5e supports speeds up to 1 gigabit per second, which is what most home internet plans deliver. Cat6 supports higher speeds and is slightly more resistant to interference, but the difference matters only if you have gigabit internet or faster and plan to move large files between computers on your home network.

Buy from a hardware store, electronics retailer, or online marketplace. Avoid extremely cheap cables from unknown sellers, as they may have poor shielding or loose connectors.

If your computer does not have an ethernet port

If your computer has no built-in ethernet port, you can add one using a USB ethernet adapter. These are small devices that plug into a USB port on your computer and have an ethernet jack on the other end. They cost between $15 and $40 and work with Windows, Mac, and Linux machines.

Plug the adapter into an available USB port on your computer. Windows and Mac both recognize USB ethernet adapters automatically in most cases. Once the adapter is connected, plug your ethernet cable into the adapter's jack the same way you would plug it into a built-in port.

If your computer does not recognize the adapter, visit the manufacturer's website and read the driver for your operating system. This is rare but can happen with older adapters or less common brands.

Troubleshooting a connection that does not appear

If you plug in the cable and your computer does not show a connection within 30 seconds, first check that both ends of the cable are fully seated — push them in again until you feel the click.

Next, check that the port on your router is working. Unplug the cable from your computer and plug it into a different port on the router. If that works, the first port may be faulty. If nothing works, restart your router by unplugging it for 10 seconds, then plugging it back in.

On Windows, open Settings, go to Network & Internet, and check the status under Ethernet. If it says "No internet connection" but shows the cable is plugged in, restart your computer. On Mac, go to System Preferences, click Network, and select Ethernet from the list on the left. If it shows "Connected", your computer is online.

If the cable itself is damaged — bent, kinked, or visibly frayed — replace it. Ethernet cables are cheap and wear out.

Ethernet versus Wi-Fi: when to use each

Ethernet is faster and more stable than Wi-Fi, so use it for activities that demand a steady connection: online gaming, video calls, large file uploads or downloads, and streaming video. It is also the better choice if your Wi-Fi signal is weak in the room where your computer sits.

Wi-Fi is more convenient when you move your computer around the house or want to avoid running cables. If your internet speed is under 100 megabits per second, the difference between ethernet and Wi-Fi is small enough that you may not notice it. If your speed is higher or you do bandwidth-heavy work, ethernet will feel noticeably faster.

You can use both at the same time — your computer will prioritize ethernet and fall back to Wi-Fi if the cable is unplugged — but there is no reason to. Pick one and stick with it.

Frequently Asked Questions

Does ethernet slow down if I use a very long cable?

No. Ethernet cables up to 100 meters (about 330 feet) work at full speed. Beyond that, the signal degrades. For home use, cable length is not a practical concern.

Can I use an ethernet cable that is already plugged into another device?

No. Each cable can only connect one device to the router at a time. If you need to connect multiple computers, you need multiple cables or a network switch, which is a small box that gives you more ethernet ports.

What if my router is in another room and I cannot run a cable there?

You have two options: use Wi-Fi instead, or buy a longer ethernet cable and run it along the baseboards or through walls if you are comfortable doing that. Some people use cable conduit or raceways to hide cables neatly.

Do I need to restart my computer after plugging in the ethernet cable?

No. Your computer recognizes the connection when ready in almost all cases. If it does not show up after 30 seconds, restart your computer or your router, but not as a first step.

Is ethernet safer than Wi-Fi?

Ethernet is more private because the data travels through a physical cable that only your computer and router can access. Wi-Fi broadcasts through the air, so someone nearby could theoretically intercept it. For everyday use, Wi-Fi security is strong enough if your router has a password, but ethernet adds an extra layer of privacy.