This article explains how to change your DNS servers on an Android phone for faster, more secure wireless connections. Instructions apply to Android 9 (Pie) and later, as well as Android 8 (Oreo), but the process is similar on older Android versions.
How to Change DNS Server in Android for Mobile Data and WiFi
It’s pretty easy to change DNS address on Android 9 and above. Instead of changing addresses per network, you can set alternate DNS addresses in a single location. Follow these steps to manually change DNS:
Open your phone's Settings and tap Network & Internet.
Tap on Private DNS, then select Private DNS provider hostname and enter the Cloudflare URL or one of the CleanBrowing URLs in the text field. You can find them in the section below.