What Do The Lights On An Ethernet Port Mean?

If you've ever glanced at the back of your router, you might have noticed tiny LED lights next to the Ethernet port. Your Ethernet port is a physical interface found on routers and some other devices like modems, network switches, and Network-Attached Storage devices. It allows for wired connections using Ethernet cables. We'll mostly refer to router Ethernet ports in this article, because if you're checking the status of an Ethernet port, a router is the most likely device, but the information here will be applicable to other devices as well.

Even if you usually use W-Fi to connect to the internet, you'll likely use Ethernet cables occasionally. It can be a handy way to speed up your internet, as it's less susceptible to interference than Wi-Fi. You may also need to use the Ethernet on your router if you're testing your internet speeds or troubleshooting connection problems. Understanding Ethernet port lights means you can check your connectivity and diagnose issues that might be stopping your devices from communicating effectively.

Not all Ethernet ports have lights. It depends on the make and model of your router. Generally, however, if you look at the back of your router, you'll see two lights next to the Ethernet port. One indicates the status of the connection, and the other shows data transmission activity.

The connection light should be a solid, unblinking light indicating that your router is successfully connected to your laptop or other device via the Ethernet cable. On most routers, it's a green light, but it can be a different color. Some devices use multiple colors to represent the speed of the connection.

The other light shows whether the router is connected to the internet. If it is working correctly, the light should be quickly blinking on and off to indicate that your router is actively talking to the internet. Every time the light blinks, your router is either sending out information (like when you click on a website) or receiving information (like when that website loads on your screen).

There are two scenarios where your lights can indicate a problem. The first is that the connection light is on, but the activity light isn't. The other is that both lights are off. It is pretty much impossible for the activity light to be on if the connection light isn't, because any internet activity needs a working connection.

If the connection light is on but the data activity light is off, it means that your device is physically connected to the router and the connection is working, but no data is currently being sent or received through that connection. This isn't necessarily a bad thing. It could be that you're just not actively using the internet at that time. However, if you're trying to connect to the internet and the data activity light isn't on (and the connection light is), this indicates that although the router is connected to your device, the internet connection itself is down. This may be because your Internet Service Provider is having issues or because of problems with your router. 

If neither light is on, that means there is no active connection. This could be due to a disconnected cable, a powered-off device, or a malfunctioning port. If you're having problems with your connection, take a look at the router's manual or, alternatively, read our guide to troubleshooting Ethernet issues.