Open-source DNS resolvers

3 DNS resolvers whose code is public under an OSI-approved license, rated for privacy with evidence. Picks first, then by score.

1. Unbound Grade B

   Validating, recursive and caching DNS resolver from NLnet Labs for running your own resolver, with DNS over TLS and DNS over HTTPS support.

   BSD-3-Clause. Source code

2. LibreDNS Grade C

   Public encrypted DNS resolver run by the volunteer LibreOps collective, with DoH and DoT endpoints and an optional ad-blocking endpoint.

   The server deployment scripts are published under AGPL-3.0 and run open-source DNS software. Source code

3. AdGuard Grade C

   Public DNS resolver from AdGuard that blocks ads, trackers and malicious domains, with open-source server software and DoH, DoT, DoQ and DNSCrypt support.

   AGPL-3.0. Source code

Compare all 18 DNS resolvers, open source or not.