Should WiFi routers be set to a channel or choose automatically?

Solution 1:

It really depends on a couple of things:

1. Is it s really nice router? If so, it will probably do proper channel selection based on local usage/interference, and may even recheck when it restarts, in which case you probably want it set to auto-selection. If it's a cheap router though, 'Auto' is almost always one of a couple predefined channels (for example, in the 2.4GHz band in the US, 'Auto' usually means channel 1 or channel 8, or on rare occasion channel 6 or 11), and in that case check the next point.
2. How much interference are you actually seeing? Ideally, grab a Wi-Fi signal analyzer app for your phone, and see what channels are being actively used in your area. If your router is auto-selecting a channel that's in active use by just one other AP and that other AP has a weaker signal in the entire area you want covered, you're probably fine. If on the other hand you see multiple other AP's on that channel or another AP has a stronger signal than your router does in an area you need covered, you should probably look at manually specifying a channel instead of just letting the router choose one.
3. As a special case, if you're using WoWLAN (Wake on Wireless LAN) on your network, you almost certainly want to go to the trouble of specifying a channel manually regardless, as WoWLAN will stop working if your router changes the channel while a device is offline, and any interference can cause issues with WoWLAN.

Also, just a general tip when choosing a channel manually, try to find one that is as far from any other used channels as possible. With a few special exceptions like channel 14 in the 2.4GHz band most channels partially overlap at least one other channel, so being as far from other channels that are in-use as possible will help reduce interference.

Solution 2:

The answer depends on the router.

If you have a nice, quality router with updated firmware, "Auto" will do a quick scan for what channels have the least interference, and pick from the best option.

If you have a cheap router, it usually defaults to channel 6 or 8 if you choose Auto. Since that's what most people have, you end up with a whole neighborhood living on the same channel and wondering why their internet connection sucks, even though the ISP keeps telling them they're getting full speed when they test from the Modem.

I recommend getting an app for your cell phone that will tell you how many different wifi broadcast signals it detects per channel. I use one on my android device that shows me a graph of each device's strength from my location, and the Network Identifier for the device. Using this, I was able to discover that my neighbor's irritating WiFi speakers in his back yard were single-handedly tanking most of the connections for the surrounding houses on channel 6. I manually set my 2.4ghz bandwidth connection around this until I moved up to a 5ghz router, which put me well outside of locally used frequencies.

Solution 3:

My opinion is to have them set up to automatic.

When most modern routers assign a channel, they do so by scanning the band and choosing one with the least interference. Setting yours manually would cause issue if there is already nearby routers on that channel, but when those others reset it will likely choose another channel.

Bear in mind though that here the frequency is more important. If you're running 2.4GHz, there's only three non-overlapping channels, so interference is likely regardless. Stick to the 5GHz and you should be fine.