Quad9 is a free DNS recursive service that blocks lookups of malicious host names from an up-to-minute list of threats, protecting against malware, phishing, spyware, and botnets, while guaranteeing privacy. The service is operated by the Swiss-based Quad9 Foundation, with a mission to provide a safer and more robust Internet for everyone. Quad9 protects user privacy by not logging IP addresses, employing encryption, and being GDPR-compliant. The service is dedicated to keeping personal data under the control of the end user.
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