As you may know, most WiFi devices in use today broadcast information on the 2.4 GHz and 5 GHz bands.
Each of these two bands occupies a certain frequency range. This range is then subdivided into multiple channels that are spaced apart evenly to allow multiple routers located in the same area to claim their own part of the radio frequency spectrum. As such, a WiFi channel is basically a small section of a frequency band.
To understand the difference between, you can imagine the 2.4 GHz and 5 GHz frequency bands as highways with multiple lines (channels). The advantage of having multiple lines to choose from is that as long as there’s at least one empty line, you can safely pass everyone else and reach your destination on time.
Now that you have a basic understand of what WiFi channels are, we can take a closer look at the two most commonly used WiFi bands:
2.4 GHz band: In North America, the 2.4 GHz band is divided into 11 channels. Because of its lower frequency, signals in the 2.4 GHz band have a fairly good ability to penetrate solid objects, such as walls and furniture, allowing them to cover a larger range with a strong WiFi signal. In addition to WiFi devices, this band is used by cordless phones, baby monitors, Bluetooth gadgets, and many other electronic devices, all of which can cause interference and slowdowns.
5 GHz band: In recent years, many manufacturers of WiFi routers have released models with support for the 5 GHz band to combat issues with interference on the 2.4 GHz frequency band. Because of its higher frequency, signals in the 5 GHz band don’t penetrate solid objects as well as signals in the 5 GHz band, and they also benefit from a much larger number of available channels. In fact, you can imagine the 5 GHz band as several highways stacked on top of one another, each reserved for different vehicles and divided into multiple lines.
While the 5 GHz band has 24 non-overlapping channels, the 2.4 GHz band has only three non-overlapping channels: 1, 6, and 11.
To make matters worse, not all WiFi routers and their users know that they should be using only non-overlapping WiFi channels because the use of any other WiFi channel is guaranteed to result in adjacent-channel interference.
Why does the use of other WiFi channels results in adjacent-channel interference? Because channels in the 2.4 GHz band have a WiFi channel width of 20 MHz, which would be fine if they were not spaced only 5 MHz apart. As a result, channel 3, for example, overlaps with both channels 1 and 6, and the same is true for channels 2, 4, and 5. Likewise, channels 7, 8, 9, and 10 overlap with channels 6 and 11.
Users sometimes believe that the best WiFi channel is the one that’s used the least, which is why they end up picking an overlapping channel and cause more harm than good. To really find the best channel for WiFi, you need a WiFi channel analyzer or scanner and a little bit of know-how.
In public spaces, apartment buildings, offices, and other densely populated areas, it’s very common for multiple WiFi routers to broadcast simultaneously on a single non-overlapping channel. In such situations, your best option is to use a WiFi channel scanner or analyzer and find the least crowded non-overlapping channel.
To determine which non-overlapping WiFi channel is the best, you need to consider RSSI and noise values. The former stands for “Received Signal Strength Indicator,” and indicates how well a WiFi-enabled device can receive signals from a WiFi router. Noise indicates how much interference caused by other signals affects the particular connection.
RSSI is indicated in negative numbers, and the closer it is to zero the better because zero means that no signal strength has been lost during transmission. For example, an RSSI of -50 is better than an RSSI of -60. With noise, you want to get as far away from zero as possible, so -90 is better than -80.
It’s also very useful to combine the two values and calculate something that’s called Signal-to-Noise Ratio (SNR), a measure used in science and engineering that compares the level of the desired signal to the level of background noise.
To calculate the SNR of a WiFi connection, all you need to do is subtract the value of noise from the RSSI:
RSSI — noise = SNR → (-50) - (-90) = 40
The result is a positive number, and the higher the number is, the better WiFi speeds you can expect.
Now that you know how to calculate the SNR of your WiFi connection, it’s time to switch between channels 1, 6, and 11 and select the one that allows you to achieve the highest SNR.
If this sounds like a lot of work, you need a WiFi channel analyzer like NetSpot, which can calculate everything for you and instantly give you all the information you need to decide which WiFi channel is the best.
Now that you understand the theory behind finding the best WiFi channel, it’s time to take a closer look at how to do it in practice on every major platform.
If you decide that the steps described below are a lot of work, you can skip to the next section, where we describe how to use a WiFi channel analyzer like NetSpot, which can calculate everything for you and instantly give you all the information you need to decide which WiFi channel is the best. Best of all, NetSpot runs on most major platforms, and it delivers reliable results with minimal effort.
As a macOS user, you have two main options on how to find the best WiFi channel: the Wireless Diagnostics feature and NetSpot.
Wireless Diagnostics is a feature of macOS that lets you see all networks in your area, along with basic information about them:
NetSpot for macOS
NetSpot is a third-party WiFi channel scanner with lots of useful, easy-to-use features that make one of the best WiFi channel scanner apps for macOS. Here’s how it works:
Finding the best channel for WiFi on Windows without a third-party app can be a bit daunting because the tool provided by Microsoft doesn’t have a graphical user interface. Fortunately, third party WiFi channel scanners like NetSpot do.
If you’re not afraid of the command line, then you can discover how often are different WiFi channels used by issuing the following command:
netsh wlan show all
NetSpot for Windows
Alternatively, you can use the Windows version of NetSpot, one of the best WiFi channel scanner apps for Windows.
Gathering information about WiFi channel utilization on most Linux distributions, including Ubuntu and Linux Mint, is a matter of entering the following command in your favorite terminal emulator:
sudo iwlist wlan0 scan | grep \(Channel
Instead of displaying all kinds of unnecessary information about each network, the command displays only a list of channels.
The Android operating system doesn’t provide a native feature that would let you find the best WiFi channel scanner for Android. Fortunately, you can download NetSpot for Android directly from the Google Play Store and use it to find the best WiFi channel with a few taps:
Apple provides its own utility, called AirPort Utility, and you can use it to discover the best WiFi channel available in your area. Alternatively, you can download a third-party WiFi Channel Scanner for iOS like NetSpot to enjoy advanced features and more comprehensive scan results.
NetSpot for iOS
NetSpot is a powerful WiFi channel analyzer for Windows 10, 8, and 7, and for macOS 10.10 and higher. It can quickly gather all information about WiFi channels and surrounding WiFi networks, including their RSSI and noise values.
After taking a snapshot of surrounding WiFi networks, NetSpot is able to locate the busiest and least occupied channels, helping you decide which channel you should configure your WiFi router to use. To do that:
When using NetSpot to find the best WiFi channel, you need to keep in mind that your ultimate goal is to avoid co-channel interference, which occurs when two or more WiFi routers operate on the same channel or neighboring channels.
Here are some basic WiFi channel planning best practices to help you achieve this goal:
By following these three simply WiFi channel planning best practices, you should be able to achieve the best download and upload speeds possible and avoid issues with latency, signal interference, and coverage.
Use NetSpot to verify that the router is broadcasting on the new channel. It’s useful to try more than one WiFi channel and compare the SNR of your WiFi connection.In addition to helping you find the best WiFi channel, NetSpot can also perform a WiFi site survey, create a detailed WiFi coverage map, help you discover areas of signal weakness, highlight all sources of WiFi interference, and much more.
In most situations, the best WiFi channel is the one with the lowest number of users, assuming all users broadcast a roughly equally strong WiFi signal.
Generally, you want to focus your attention on channels 1, 6, and 11 because these are the only non-overlapping channels in the 2.4 GHz band. Using a WiFi channel scanner, discover how many users each of these three channels has and pick the one that’s used the least.
You should use the channel with the lowest number of users. If you discover multiple suitable channels, then we recommend you use the lowest one because lower-frequency channels penetrate solid obstacles, such as well, better than higher-frequency channels.
You can easily find the best WiFi channel for Windows 10 using a third-party WiFi channel scanner like NetSpot. Thanks to its graphical user interface, finding the best WiFi channel is something even complete beginners can do with no effort at all.