In your router's settings there are channel settings. Most routers have channel settings set to "Auto", but if you look through the list, there are at least a dozen of WLAN channels. So how do you know which WiFi channels are faster than the others in that list? Choosing the proper WiFi channel can vastly improve your WiFi coverage and performance. But even if you find the fastest channel there it doesn't always mean you should select it right away.

Various frequency bands (2.4GHz, 3.6 GHz, 4.9 GHz, 5 GHz, and 5.9 GHz) have their own range of channels. Usually routers will use the 2.4GHz band with a total of 14 channels, however in reality it may be 13 or even less that are used around the world. All Wi-Fi versions through 802.11n (a, b, g, n) work between the channel frequencies of 2400 and 2500 MHz. These 100 MHz in between are split in 14 channels 20 MHz each. As a result, each 2.4GHz channel overlaps with two to four other channels (see diagram above). Overlapping makes wireless network throughput quite poor.

Most popular channels for 2.4 GHz Wi-Fi are 1, 6, and 11, because they don’t overlap with one another. You should always try using channels 1, 6, or 11 when on a non-MIMO setup (i.e. 802.11 a, b, or g).

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