There are several options of publicly accessible DNS servers that offer content filtering and/or ad blocking.

DNS based filtering often lacks the level of customization that an installed filtering application offers, but is generally a high performance solution and can be used on routers to filter all devices that connect to your WiFi.

Below are some server options and the categories they filter.

OpenDNS Family Shield208.67.220.123
208.67.222.123		Malware
Scam
Phishing
Adult Content
Neustar DNS - Moderate156.154.70.3
156.154.71.3		Malware
Spyware
Gambling
Violence
Discrimination
Ransomware
Phishing
Pornography
Hate
Neustar DNS - Strict156.154.70.4
156.154.71.4		Malware
Scam
Adult Content
Alcohol
Drugs
Gambling
Suicide
Phishing
Pornography
Abortion
Crime
File Sharing
Hate
Violence
AdGuard DNS Family94.140.14.15
94.140.15.16		Ads
Adult Content
Phishing
Yandex.DNS Family77.88.8.7
77.88.8.3		Malware
Scam
Phishing
Pornography
RETIRED - Norton ConnectSafe (Moderate & Strict)x.x.x.xNorton is retiring their ConnectSafe DNS service in November 2018. Anyone using this service will need to move to another provider.

Note: You should only use a DNS server you trust.

To use DNS Filtering on Windows PCs

Note: An administrator account on the computer can disable the filtering. For this reason (and it’s generally a more secure computing habit anyway) the main user accounts should be “Standard Users.” This will require the supplying of the administrator account password to install programs, change system level settings, etc.


Step One: Press the Windows Key and the letter ‘R’ on the keyboard to open the Run dialog.

Step Two: Type ncpa.cpl in the Run box and press the Enter key

This will open the list of network adapters on the computer

Step Three: Right-click the WiFi Adapter in the list (or the Ethernet adapter if you use wired connection for your home internet; do the same steps to both if you switch periodically between connection methods) and click Properties

Step Four: Uncheck Internet Protocol Version 6 (IPv6)

Step Five: Highlight Internet Protocol Version 4 (IPv4) and click the Properties button

Step Six: Select the option “Use the Following DNS Server Addresses” and enter the addresses of the service you wish to use.

Android

Step One: Install The Blokada 5 app Blokada.org

Step Two: Open Blokada and go to the Advanced section

Step Three: Tap Networks

Step Four: Tap All Networks

Step Five: Tap the DNS option under Configurations

Step Six: Choose the appropriate DNS filtering provider

iOS (Apple iPhone and iPad)

Step One: Install DNSCloak from the App Store

Step Two: Open the DNSCloak App

Step Three: Select the provider you want and poke the Start button at the top of the list.

My preferences are OpenDNS FamilyShield and AdGuard Family