How to check my laptop WiFi frequency on Linux 2023

Here are some useful Linux commands you need if you want to determine what frequencies your computer supports and check if you can use 5G WiFi.

This command will show you all the channels supported by your network card and on which frequency they work.

Let’s first find out which network interface your card uses, open Terminal and type:

iwconfig

This is an example from my computer, I have two network cards, one is wlan0 and the other is wlan1:

$ iwconfig
lo        no wireless extensions.

eth0      no wireless extensions.

wlan0     IEEE 802.11  ESSID:off/any  
          Mode:Managed  Access Point: Not-Associated   Tx-Power=22 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          
wlan1     IEEE 802.11bgn  ESSID:"vojin"  Nickname:"<WIFI@REALTEK>"
          Mode:Managed  Frequency:2.462 GHz  Access Point: 58:96:30:97:25:A0   
          Bit Rate:72.2 Mb/s   Sensitivity:0/0  
          Retry:off   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=90/100  Signal level=90/100  Noise level=0/100
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

wwan0     no wireless extensions.

Open Terminal and type the following command to check if you can use 5G WiFi, depending on which interface your network card uses, use the wlan0 or wlan1 option in the command:

iwlist wlan0 channel

or

iwlist wlan1 channel

In case you get a result like this:

$ iwlist wlan0 channel
wlan0     13 channels in total; available frequencies :
          Channel 01 : 2.412 GHz
          Channel 02 : 2.417 GHz
          Channel 03 : 2.422 GHz
          Channel 04 : 2.427 GHz
          Channel 05 : 2.432 GHz
          Channel 06 : 2.437 GHz
          Channel 07 : 2.442 GHz
          Channel 08 : 2.447 GHz
          Channel 09 : 2.452 GHz
          Channel 10 : 2.457 GHz
          Channel 11 : 2.462 GHz
          Channel 12 : 2.467 GHz
          Channel 13 : 2.472 GHz

and (my second card):

$ iwlist wlan1 channel
wlan1     13 channels in total; available frequencies :
          Channel 01 : 2.412 GHz
          Channel 02 : 2.417 GHz
          Channel 03 : 2.422 GHz
          Channel 04 : 2.427 GHz
          Channel 05 : 2.432 GHz
          Channel 06 : 2.437 GHz
          Channel 07 : 2.442 GHz
          Channel 08 : 2.447 GHz
          Channel 09 : 2.452 GHz
          Channel 10 : 2.457 GHz
          Channel 11 : 2.462 GHz
          Channel 12 : 2.467 GHz
          Channel 13 : 2.472 GHz
          Current Frequency:2.462 GHz (Channel 11)

This means that your network card only supports signals around 2.4 GHz and cannot use 5G WiFi which works at around 5 GHz.

In this case, your computer does not support 5G WiFi.

In order to be able to use 5G WiFi on your computer, the solution is either to buy a USB internet adapter that supports 5G WiFi or to try this solution: How to use 5G WiFi if your laptop only supports 2.4 GHz frequency