AdGuard DNS vs Quad9

AdGuard DNS has no write-up on Specifiction yet; its figures are above.

Quad9 is a free recursive DNS service that blocks requests to domains associated with malware, viruses, adware, phishing and scams. It draws on threat information from more than 20 partners to identify malicious domains. The service supports DNS over TLS, DNS over HTTPS and DNSCrypt, and provides DNSSEC validation on its resolver services. Quad9 says it does not store end-user IP addresses and operates under Swiss privacy law. Its focus is malicious-domain blocking, not content filtering; it also does not offer custom domain policies. Setup documentation covers Cloudflared, Pi-hole and open-source routers including pfSense, OPNsense, OpenWrt, MikroTik RouterOS and IPFire. Support assists with setup questions and issues. Quad9 reports 99.999% uptime for its global anycast service. The service costs nothing, with no contract or sign-up process, and is listed for Android, iOS, Linux, macOS and Windows. Large organizations planning high-volume DNS traffic are asked to contact Quad9 first.