Why Changing the Wi-Fi Channel Number Avoids Interference

Wireless home networks transmit signals in a narrow radiofrequency range around 2.4 GHz, and it's common for devices on the same frequency to affect the wireless signal and slow down an internet connection. Electronics such as cordless phones, garage door openers, baby monitors, and microwave ovens may use this frequency range. The wireless networks of neighbors may use the same radio signaling that interferes with an internet connection, especially in residences that share walls.

If your electronic devices or your neighbor's network slow down your home network and internet connection, change the wireless channel on your router to communicate on a different frequency to avoid interference.

How Wi-Fi Channels Work

The 2.4 GHz Wi-Fi signal range is divided into several smaller bands or channels, similar to television channels. In most countries, Wi-Fi network equipment provides a set of available channels from which to choose.

For example, in the United States, any of the Wi-Fi channels 1 through 11 can be chosen when setting up a wireless LAN (WLAN). Strategically setting this channel number can help avoid sources of wireless interference.

Which 2.4 GHz Wi-Fi Channel Is Best?

Wi-Fi equipment in the U.S. often ships with its default Wi-Fi channel set to 6. If you encounter interference from other devices in your home, change the channel up or down to avoid it. However, all Wi-Fi devices on a network must use the same channel.

Unlike television channels, some Wi-Fi channel numbers overlap with each other. Channel 1 uses the lowest frequency band, and each subsequent channel increases the frequency slightly. Therefore, the further apart two channel numbers are, the less the degree of overlap and likelihood of interference. If you encounter interference from a neighbor's WLAN, change to a more distant channel.

The three Wi-Fi channels 1, 6, and 11 have no frequency overlap with each other. Use one of these three channels for the best results.

Which 5 GHz Wi-Fi Channel Is Best?

Newer 802.11n and 802.11ac Wi-Fi networks also support 5 GHz wireless connections. These frequencies are less likely to encounter wireless interference issues in homes the way 2.4 GHz does. The 5 GHz Wi-Fi channel choices available in most home network equipment are selected to choose only non-overlapping channels.

Choices vary by country, but in the United States, the most recommended non-overlapping 5 GHz channels are 36, 40, 44, 48, 149, 153, 157, and 161.

Usable non-overlapping 5 GHz channels also exist between 48 and 149, specifically 52, 56, 60, 64, 100, 104, 108, 112, 116, 132, and 136. These channels fall into a specially regulated category where a Wi-Fi transmitter detects whether other devices are transmitting on the same channel and automatically changes its channel to avoid conflict.

While this Dynamic Frequency Selection (DFS) feature avoids interference issues, many network administrators avoid using these channels to minimize complications.

How to Find or Change the Wi-Fi Channel You're Using

To find the wireless channel your router uses, log in to the router administration page, usually at the router IP address. Look for something referring to wireless channels or WLAN.

To see the wireless channel setting, use a mobile or desktop wireless app. These Wi-Fi apps point out your network's channel and the WLANs that your device can see in the range.

The ability to see nearby wireless networks and their channels is crucial. You need to know what the other channels are set at so that you know which channel to change.

Change Your Wi-Fi Channel but the Internet Still Slow?

Wireless interference is only one of several possible causes of a slow network connection. If changing the wireless channel didn't do the trick, there are more troubleshooting steps you can try to fix a slow internet connection.