The steps of the PC side are as follows:
1.Click the network icon in the bottom right corner on the system desktop.
2.Click [Network and Internet settings] in the pop-up box.
3.Click WLAN on the left handside.
4.Click [Hardware Properties] under [WLAN].
5.Then you will see the information of network band.
The steps for viewing on the mobile side are as follows:
Android：
Different brands of Android phones are different. Take Huawei mobile phone as an example. You can click on the connected Wi-Fi name in the Wi-Fi list, and the corresponding information will be displayed, including the frequency.
iOS：
1.Download AirPort tool in the App Store
2.Turn on the Wi-Fi Scanner in "Settings - Airport Tools"
3.Open the app and click on “Wi-Fi Scan” in the upper right corner. Channel 1-13 band is 2.4G, and larger than 13 is 5G.