Quad9 exists to serve the privacy, security, and performance needs of our users. One of the ways we safeguard our users’ privacy is through the support of several encrypted DNS protocols which are listed below. Unencrypted methods of transmission are susceptible to snooping and man-in-the-middle attacks. Encryption can ensure no one is intercepting your DNS queries for inspection and ensures the queries that are returned are in fact from Quad9.
DNS over TLS (DoT)
DoT is an encrypted form of sending DNS queries with the TLS protocol. The DoT standard is based on RFC 7858. Quad9 uses port 853 for DoT queries.
DNS over HTTPS (DoH)
DoH is an encrypted form of sending DNS queries with the HTTPS protocol. The DoH standard is based on RFC 8484. Quad9 uses both ports 443 and 5053 for DoH queries.
DNSCrypt is a protocol that is used to authenticate communication between a DNS client and a DNS resolver such as Quad9. Please see the DNSCrypt FAQ page for more information on DNSCrypt.