Plug one end into your router, the other into your device — the cable clicks when it seats correctly

An Ethernet cable connects your router to a computer, printer, or other device using a physical wire instead of Wi-Fi. One end plugs into a port on the back or side of your router labeled with a number (1, 2, 3, or 4) or the word "LAN". The other end plugs into the Ethernet port on your device. The connection is complete when you hear a small click and see a light turn on next to the port — usually green or amber.

Ethernet is faster and more stable than Wi-Fi, which is why it matters for devices that stay in one place, like a desktop computer or a streaming box. The cable itself has no power — it only carries data — so you cannot plug it in backwards or break it by reversing the ends.

Key Takeaways

  • Ethernet cables have a connector on each end that clicks into place; if it does not click, it is not fully seated.
  • Your router has multiple numbered ports (usually 1 through 4); any of them work the same way for connecting devices.
  • The cable runs from a LAN port on the router to an Ethernet port on your device — the port names match.
  • A light next to the port turns on when the connection is live; no light means the cable is loose or the port is not working.
  • Ethernet cables come in different lengths; measure the distance from your router to the device before you buy one.

Locating the Ethernet ports on your router

Look at the back of your router. You will see several ports clustered together. The Ethernet ports are the small rectangular openings, usually grouped on one side. They are smaller than the power port and larger than a phone jack. Most routers have four Ethernet ports labeled 1, 2, 3, and 4, or sometimes labeled "LAN 1" through "LAN 4". Any of these ports work identically — the numbering is just for your reference.

Some routers also have a port labeled "WAN" or "Internet" in a different color (often yellow or blue). Do not use this port for connecting devices. The WAN port connects to your modem, not to your devices. Stick to the numbered LAN ports.

Finding the Ethernet port on your device

The Ethernet port on your computer, printer, or other device looks identical to the port on the router — a small rectangular opening. On a desktop computer, it is usually on the back near other cables. On a laptop, it may be on the side or back, though many modern laptops do not have one built in (you would need a USB adapter instead). On a printer or streaming device, check the back or bottom panel.

If you cannot find the port, check the device manual or search the manufacturer's website with your device model number. The manual will show you exactly where the port is located.

Inserting the cable and confirming the connection

Hold the Ethernet cable connector in your hand. The connector is a small plastic piece with eight tiny metal pins inside. The opening faces forward. Line it up with the port opening and push straight in until you hear a small click. The click means the locking tab on the connector has engaged. If you do not hear a click, the cable is not fully seated — pull it out and try again.

Once the cable is clicked in, look at the light next to the port on your router. Within a few seconds, a light should turn on — usually green, amber, or blue. This light means data is flowing. On your device, a light may also appear next to the Ethernet port, or a network icon on your screen may change to show a wired connection. If no light appears after 30 seconds, the cable may be damaged or the port may not be working.

What to do if the cable does not click or the light does not turn on

If the connector does not click into place, the cable may be inserted at a slight angle. Pull it out completely and look at the connector opening. Make sure nothing is blocking it — sometimes a small piece of plastic or dust can prevent the connector from seating. Align the connector straight and push again until you feel the click.

If the cable clicks but no light appears, try a different port on the router. If a light turns on at the new port, the first port is faulty but your connection is working. If no light appears at any port, the cable itself may be damaged. Test with a different cable if you have one available. If the device port is the problem, you may need a USB Ethernet adapter (a small device that plugs into a USB port and has an Ethernet port on the other end).

Choosing the right cable length and type

Ethernet cables come in lengths from 3 feet to 100 feet or more. Measure the distance from your router to the device before you buy. Add a few extra feet so the cable does not stretch tight — a taut cable can pull loose from the port. Coiled or bundled cable is fine; Ethernet does not care if the cable is straight or coiled.

For most home networks, a standard Cat5e or Cat6 cable works fine. These are the most common types and cost between $5 and $15. Cat6 is slightly faster and handles longer runs better, but for distances under 100 feet in a home, either one performs the same way. Avoid very cheap cables under $2 — they often have loose connectors that fall out easily.

Securing the cable so it does not come loose

Once the cable is connected, you can run it along the wall or floor. If you want to keep it in place and prevent it from being accidentally pulled, use cable clips or adhesive-backed cable holders. These are plastic or rubber clips that stick to the wall or screw into place, and the cable slides through them. They cost a few dollars and prevent the cable from moving around.

Do not run the cable under a rug or in a high-traffic area where people might step on it. Pressure on the cable can damage the wires inside and cause the connection to drop. If the cable must cross a walkway, use a cable cover — a plastic channel that protects the cable and prevents tripping.

Frequently Asked Questions

Can I use the same Ethernet cable for different devices?

Yes. You can unplug the cable from one device and plug it into another. The cable itself does not wear out from being moved. Just make sure the cable is long enough to reach both locations, or you will need a longer cable for the second device.

Does it matter which port on the router I use?

No. All numbered LAN ports (1, 2, 3, 4) work identically. Use whichever port is closest to your device or most convenient. Only avoid the WAN or Internet port, which connects to your modem.

What if my device does not have an Ethernet port?

You can buy a USB Ethernet adapter — a small device that plugs into a USB port on your computer or laptop and has an Ethernet port on the other end. These cost $15 to $30 and work the same way as a built-in port.

Is it safe to leave the cable plugged in all the time?

Yes. Ethernet cables carry data only, not power, so there is no risk of overheating or electrical damage. You can leave the cable connected indefinitely without any problem.

Why is my Ethernet connection slower than my Wi-Fi?

This usually means the cable or port is damaged, or the cable is very old. Test with a different cable. If the speed improves, the original cable was the problem. If speed stays the same, the port may be faulty — try a different port on the router.