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Quad9 is a public DNS resolver that blocks access to malware infected websites. The service protects privacy by not logging the IP address of users who set their computers to send queries to it.
CleanerDNS, Inc., a California non-profit corporation, operates Quad9. CleanerDNS is supported by IBM, Packet Clearing House (PCH), Global Cyber Alliance (GCA), other cyber-security organizations, and private donations. On February 17, 2021, the organization announced that it is in the process of re-incorporating its operations in the country of Switzerland, stating that the host nation's robust privacy laws better support Quad9's user data privacy initiatives.
Quad9 operates recursive name servers for public use at the following IP addresses. These addresses are mapped to the nearest operational server by anycast routing. Quad9 offers DNS over TLS over port 853, DNS over HTTPS over port 443, and DNSCrypt over port 443.
|Secured (Mainstream)||Unsecured||Secured, with ECS support|
Quad9's primary DNS service is accessible via the IP addresses for IPv4: 126.96.36.199 and 188.8.131.52, and IPv6: 2620:fe::fe and 2620:fe::fe:9. This service supports blocklist, DNS encryption, and DNSSEC.
Quad9's alternative DNS service that supports limited features is accessible on IPv4: 184.108.40.206 and 220.127.116.11, and IPv6: 2620:fe::10 and 2620:fe::fe:10. This service only supports DNS encryption.
Quad9's identical DNS service that supports ECS is accessible on IPv4: 18.104.22.168 and 22.214.171.124, and IPv6: 2620:fe::11 and 2620:fe::fe:11. This service supports blocklist, DNS encryption, DNSSEC, and ECS.
No personally-identifiable information is collected by the Quad9 system. IP addresses of end users are not stored to disk or distributed outside of the equipment answering the query in the local data center. Quad9 is a not-for-profit organization with the core charter to provide secure, fast, private DNS. Therefore there are no secondary revenue streams for personally-identifiable data.
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