URLFilterService is a free internet filtering application for Microsoft Windows operating systems. Thanks to the new namespace filtering code introduced in version 20170104, now it supports a very large set of applications. It can be used to build a  personal trusted list of internet sites helping you to avoid phishing and malware sites, ads, trackers and unwanted web content of any kind. Some of the supported applications are:
- Microsoft Edge, Internet Explorer and many Winstore apps (full http/s and dns control);
- Mozilla Firefox, Google Chrome, Opera browser, Vivaldi browser, Maxton browser, and many others (only dns requests).

UFS can also be used as a DNS sinkhole server (a sinkhole is a DNS server that has been configured to hand out non-routable addresses for all domains in the sinkhole) and can be used to block any unknown and unwanted domains. It works completely on your computer and  no data is sent outside your network except for allowed request for dns names. UFS  works both with ipv4 and ipv6 addresses, any external DNS resolver and any kind of device (tablets, phones, cameras, computers, etc). Please note: to work properly, because it works as a server accepting incoming connections on port 53 tcp/udp, you must allow local and global network communications in your antivirus and/or firewall to urlfilterservice.exe.