These are usually printed on the back of the smartphone box that came with the device. Under wireless connectivity column check for symbols with 802.11ac or WiFi 5 or sometimes you will see WiFi 5G . Alternatively you can Google the phone specs of your smartphone online from websites such as this or gsmarena.com.
Read moreWhy is my 5GHz WiFi not showing up on Android?
If the 5GHz WiFi is not showing up on your Android device, or automatically combines with the 2.4 GHz network, then it’s most likely your device doesn’t support 5GHz . Some devices may automatically combine both frequencies when they share the same name and password.
Read moreHow do I enable 5GHz on my Android?
If you wish, you can force your Android device to connect to Wi-Fi hotspots using the speedier 5 GHz frequency band. Tap Settings > Wi-Fi, tap the three-dot overflow icon, then tap Advanced > Wi-Fi Frequency Band . Now, pick a band: either 2.4GHz (slower, but longer range) or 5GHz (faster, but shorter range).
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