URLfilterDB offers various internet filter solutions. 

ufdbGuard for Squid works with the Squid web proxy and is an internet filter with many features.  Both Squid and ufdbGuard for Squid are Free Open Source Software.

ufdbGuard for DNS is a plugin for the BIND DNS server and makes it a filtering DNS server.

For solution providers and other businesses there are various products:
ufdbGuard API is a URL classifier in a C library,
ufdbGuard REST API a URL classifier with a REST interface,
Query Server a URL classification server to support filtering on smartphones and small devices,
Technology Package has a substantial part of our intellectual property.

All products do not track users, not even with "anonymised data".  The products only keep track of new URLs which are not yet part of the URL database, and has a few counters for statistical purposes.

ufdbGuard for Squid is Free Open Source Software   and can also be downloaded from SourceForge