How to Choose the Best Wi-Fi Channel Number
In many environments, Wi-Fi connections perform equally well on any channel. Sometimes, the best choice is to leave the network set to defaults without any changes. Performance and reliability of connections vary across channels, however, depending on the sources of radio interference and the frequencies. No single channel number is inherently best relative to the others. In the U.S., for example, some people prefer to set their 2.4 GHz networks to use the lowest possible (1) or highest possible channels (11) to avoid mid-range frequencies because some home Wi-Fi routers default to the middle channel 6. However, if neighboring networks do the same, interference and connectivity conflicts result. In extreme cases, you may need to coordinate with your neighbors on the channels each uses to avoid mutual interference. More technically inclined home admins run network analyzer software to test a local area for existing wireless signals and identify a safe channel based on the results. The WiFi Analyzer app for Android is a good example of such an application. It plots the results of signal sweeps on graphs and recommends appropriate channel settings at the push of a button. Less technical people may test each wireless channel individually and choose one that seems to work best. Often, more than one channel works well. Because the effects of signal interference vary over time, the best channel one day may turn out later not to be a good choice. Periodically monitor your environment to see if conditions have changed such that a Wi-Fi channel update makes sense.
How to Change Wi-Fi Channel Numbers
To change channels on a home wireless router, log in to the router’s configuration screens and look for a setting called Channel or Wireless Channel. Most router screens provide a drop-down list of supported channel numbers. Other devices on a local network auto-detect and adjust their channel numbers to match the router or wireless access point with no action needed. However, if certain devices fail to connect after changing the router’s channel, visit the software configuration utility for each of those devices and make matching channel number changes there. The same configuration screens can be checked at any time to verify the numbers in use.
2.4 GHz Wi-Fi Channel Numbers
Wi-Fi equipment in the U.S. and North America features 11 channels on the 2.4 GHz band:
Channel 1 operates at a center frequency of 2.412 GHz.Channel 11 operates at 2.462 GHz.Other channels operate at frequencies in between, evenly spaced at 5 MHz (0.005 GHz) intervals.Wi-Fi gear in Europe and other parts of the world also supports channels 12 and 13 running at the next-higher frequency levels of 2.467 GHz and 2.472 GHz, respectively.
A few additional restrictions and allowances apply in certain countries. For example, 2.4 GHz Wi-Fi technically supports 14 channels, although channel 14 is only available for old 802.11b equipment in Japan. Because each 2.4 GHz Wi-Fi channel requires a signaling band roughly 22 MHz wide, radio frequencies of adjacent channels significantly overlap each other.
5 GHz Wi-Fi Channel Numbers
The 5 GHz band offers more channels than 2.4 GHz Wi-Fi. To avoid problems with overlapping frequencies, 5 GHz equipment restricts available channels to certain numbers within a larger range. This approach is similar to how AM and FM radio stations within a local area keep separation between each other on the bands. For example, popular 5 GHz wireless channels in many countries include 36, 40, 44, and 48, while other numbers in between are not supported. Channel 36 operates at 5.180 GHz with each channel offset by 5 MHz, so that Channel 40 operates at 5.200 GHz (20 MHz offset), and so on. The highest-frequency channel (165) operates on 5.825 GHz. Equipment in Japan supports a different set of Wi-Fi channels that run at lower frequencies (4.915 to 5.055 GHz) than the rest of the world.
Reasons to Change Wi-Fi Channel Numbers
Many home networks in the U.S. use routers that, by default, run on channel 6 on the 2.4 GHz band. Neighboring Wi-Fi home networks that run over the same channel generate radio interference that can cause network performance slowdowns. Reconfiguring a network to run on a different wireless channel helps minimize these disruptions. Some Wi-Fi gear, particularly older devices, may not support automatic channel switching. Those devices can’t connect to the network unless their default channel matches the local network’s configuration.
