In our daily network usage, WiFi routers are essential devices for connecting to the Internet. While wireless connectivity is widely used, the RJ45 ports on WiFi routers play a crucial role that should not be overlooked. Let's delve into all aspects of RJ45 ports on WiFi routers.​

What is the RJ45 Port on a WiFi Router?​

RJ45 is an Ethernet cable interface, typically featuring 8 pins. It is a standard connector used for wired Ethernet connections. The port is slightly larger than a telephone jack and has a clip on the top to secure the Ethernet cable in place.

Functions of RJ45 Ports on a WiFi Router​

• WAN Ports: These ports, labeled "WAN" (Wide Area Network), connect to a modem, fiber ONT, or broadband gateway via an RJ45 cable, enabling the router to access the Internet.

• LAN Ports: These ports, labeled "LAN" (Local Area Network), are used to connect devices such as computers, TVs, printers, and game consoles to a network. They distribute the internal network connection, providing stable wired transmission within your local network. In addition to home and office use, LAN ports are also utilized in outdoor or temporary setups—for instance, wireless client routers can receive remote WiFi signals and output them through an RJ45 LAN port to connect surveillance cameras or point-of-sale terminals, ensuring reliable wired access even in complex environments.

Key Benefits of Ethernet Ports on a WiFi Router​ Compared to Wireless Connections

• Stronger Anti-Interference: Wired connections via Ethernet ports are not affected by physical obstacles like walls or electromagnetic interference from other electronic devices, generally ensuring a more stable connection compared to wireless.​

• Exclusive Bandwidth: Each device connected via an Ethernet port gets exclusive bandwidth. Even when multiple devices are connected simultaneously, the transmission speed of each wired device remains unaffected, unlike wireless connections which share bandwidth.​

• Extremely Low and Stable Latency: Wired connections offer minimal latency with little to no fluctuation, making them ideal for online gaming, video conferencing, and other applications that require real-time data transmission.​

• More Secure Physical Access: With a wired connection, there is minimal risk of signal leakage, reducing the chances of unauthorized access to your network. Physical access to the port is required, adding an extra layer of security.​

• Stable Long-Distance Transmission: Ethernet cables can transmit data over longer distances without significant signal degradation, ensuring a reliable connection even for devices far from the router.​

• Compatibility with Older Devices: Many older devices still rely solely on wired connections. Ethernet ports on the router allow these devices to connect to the network, extending their usability.​

Selection of WiFi Routers with RJ45 Ports​

When choosing a Wi-Fi router with RJ45 ports, consider two key factors: how many devices need wired connections and what types of Ethernet ports are required.

For typical home or office use, select a router with enough RJ45 LAN ports to match the number of wired devices—if you have 2 devices, choose a router with at least 2 LAN ports. Also, make sure the router includes an RJ45 WAN port, which is essential for connecting to your broadband modem or gateway.

If you rely on mobile networks—such as during outdoor travel, at construction sites, or in temporary retail setups—consider using a 4G or 5G router with RJ45 ports. Make sure it has enough LAN ports to support your wired devices. If LAN ports are limited, some cellular routers with built-in Wi-Fi modules can still connect multiple devices wirelessly. Also, if you plan to switch to wired broadband in the future, ensure the router includes an RJ45 WAN port for compatibility.

Taking both current and future needs into account will help you build a stable and flexible wired network, whether you're at home or on the move.

How to Add Extra Ports to Your Router if You Need Additional Connections?

If you find that your router's RJ45 ports are insufficient, you can add extra ports by using an Ethernet switch. A switch is a device that expands the number of available Ethernet ports. Simply connect one end of an Ethernet cable from a LAN port on the router to the switch, and then connect your devices to the additional ports on the switch. Switches come in various port counts, from 4-port to 24-port or more, allowing you to easily expand your network as needed.​

FAQs​

Do all wireless routers have Ethernet ports?

No, but most do. Some compact or specialized wireless routers, such as travel routers designed for portability, may lack Ethernet ports to save space. However, the majority of standard wireless routers come with both WAN and LAN Ethernet ports.​

How do I connect the Ethernet cable to the router?

First, locate the appropriate port on the router. The WAN port is usually a different color or clearly labeled. Insert one end of the Ethernet cable into the WAN port if you're connecting the router to a modem, or into a LAN port if connecting to a device. Then, insert the other end of the cable into the corresponding device (e.g., the modem for the WAN port, or a computer for a LAN port). Ensure the cable is firmly plugged in until you hear a click, indicating a secure connection.​

Wired vs. Wireless: Is an RJ45 Port Better Than WiFi?

Yes, in most cases, a wired connection via an RJ45 Ethernet port is generally preferable to a WiFi connection, particularly in terms of speed, stability, and reliability. Wired networks typically support higher and more consistent data transfer rates—particularly with Gigabit Ethernet—while wireless connections can suffer from interference, signal loss through walls, and distance limitations.

If you need a stable connection for online gaming, video conferencing, or large file transfers, wired is usually the better choice. Wireless connections offer more flexibility and mobility, but they come with trade-offs in speed and latency.

What is the maximum length of an Ethernet cable for an RJ45 port?

The recommended maximum length is 100 meters (328 feet) for standard Ethernet cables. Beyond this, signal degradation may occur, affecting connection stability and speed.​

Can I use the LAN port on my router as a WAN port?

Some routers support a WAN/LAN combo port, which means it can function as either a WAN or a LAN port depending on configuration.

Conclusion

RJ45 ports on WiFi routers may seem secondary in a wireless world, but they are vital for building stable, high-speed, and secure networks. Whether you're connecting essential office equipment, gaming consoles, or legacy devices, Ethernet ports offer unmatched reliability compared to wireless. By understanding their roles—especially the distinction between WAN and LAN ports—you can make smarter router choices, expand your wired network with switches, and ensure seamless connectivity both now and in the future.