Classy Hatter

Channel width is a router setting so it affects everyone who connects to that router. With 40 MHz channel width the maximum connection speed of 5 GHz network is between 150 and 300 Mbps, depending on which Wi-Fi version the router and devices support. If your internet connection happens to be 100 Mbps, it wouldn’t benefit having a faster Wi-Fi connection. Except that the connection quality affects the connection speed, so that 150 Mbps might be less than 100 Mbps if the device is far from the router or the connection is bad for some other reason. The connection speed is important only when downloading or uploading big files. For typical web browsing, video streaming and gaming the connection speed of few tens of Mbps is sufficient. DNS resolving speed for web browsing and ping for gaming are much more important than connection speed.

There’s probably no need to set the 5 GHz channel width to lower than 40 MHz unless the 5 GHz band is really crowded around you. 2.4 GHz should almost always be set to 20 MHz if there are other Wi-Fi networks.

Stupid Differently. Apple’s new slogan.

NetSpot and InSSIDer are often recommended. I also noticed that Apple’s AirPort Utility (iOS) can show channels and signal strength of nearby networks. You need to turn on a setting in the Settings app to enable that feature. But it doesn’t have a clear UI that would help you to figure out the best channels.

Wi-Fi extenders are usually worthless. If you want to extend your network you should use mesh network.

Another thing that helps with interference is lowering the channel width. Using wider channels gives better throughput but there will be more interference. If you don’t transfer much data between your devices wirelessly and you don’t have some crazy fast internet connection, setting the channel width to the lowest for both bands is the safest option.

Another good network troubleshooting step is to simply restart the router by unplugging the power cable for 30 or so seconds. It can fix many network related issues with little to no effort and is good practice for security reasons as well. (Restarting the router will effectively close any malware running in router and as long as the router doesn’t start them again after restart, you’ll be safe until your router is again compromised.)

Have you recently moved the router to new location or moved objects around the router? Check the router’s environment for any metal objects. They can cause significant interference. And then there are dead spots. Regardless where inside a building you place Wi-Fi access point, somewhere within its range there is most likely at least one spot where the signal cancels itself.

If the router’s location or “gaming location” has not changed, the reason most likely is that the channel used by the router has become congested. For both 2.4GHz and 5GHz there are recommended channels one should use, and you should choose the one that is least used around you. There are no tools for iOS devices that can help with that because Apple has locked down the required functionality, so use either computer or Android. EDIT: Apple’s AirPort Utility has this functionality after you enable it in Settings app.

5GHz is better for gaming due to better latency. But if you can’t play close enough to the router, 2.4GHz might provide more stable connection.