An open DNS recursive service for free security and high privacy

Quad9 is a free service that replaces your default ISP or enterprise Domain Name Server (DNS) configuration. When your computer performs any Internet transaction that uses the DNS (and most transactions do), Quad9 blocks lookups of malicious host names from an up-to-the-minute list of threats. This blocking action protects your computer, mobile device, or IoT systems against a wide range of threats such as malware, phishing, spyware, and botnets, and it can improve performance in addition to guaranteeing privacy. The Quad9 DNS service is operated by the Swiss-based Quad9 Foundation, whose mission is to provide a safer and more robust Internet for everyone.

Watch our short videos on how to set up Quad9 - Windows / MacOS ▸


Average Daily Blocks


Threat Intelligence Providers


Resolver Clusters in over 110 countries

Watch our short videos on how to set up Quad9 - Windows / MacOS ▸


How Quad9 protects your privacy

When your devices use Quad9 normally, no data containing your IP address is ever logged in any Quad9 system. Connections can employ encryption if your system supports it, and the entire Quad9 platform has been designed to be GDPR-compliant from the first public announcement in 2017.

Read more about Quad9’s privacy ▸

Why Quad9 is dedicated to data privacy

Every transaction on the Internet starts with a DNS event. This name lookup reveals critically sensitive data about the person triggering that transaction. The nature of those name lookups has created a strong and dangerous motivation for commercialization of personal data from DNS recursive resolver services. Quad9 is the only large DNS resolver with a founding charter that includes privacy as a primary goal, and the Quad9 team is devoted to the concept of keeping personal data under the control of the end user.

Quad9’s organizational move to Switzerland is important for the free and open internet because it provides much-needed geographic and legal diversity in the open DNS resolver space. It also shows that Quad9 is actively seeking to work within the legislative framework that best serves the privacy of its users. I support the Quad9 open resolver because it puts the end user first and helps build a secure and private internet without collecting – and therefore without the possibility of commercializing – users’ personal information. I believe Quad9’s philosophy of openness and transparency in handling users’ data resonates strongly with the core beliefs of our community.”

Christian Kaufmann


I’m really impressed by the privacy architecture of Quad9. In addition to providing great security as a DNS resolver, Quad9 doesn’t collect or retain personal data. Now, it is relocating to Switzerland, where it will become subject to the rigors of Swiss data protection law, which is similar to GDPR. In addition, it obtained findings of law from the Swiss government whereby it won’t be required to retain personal information, nor will it be subject to requests from law enforcement or national security”

Omer Tene

Vice President and Chief Knowledge Officer,
International Association of Privacy Professionals


How Quad9 blocks malware

Quad9 routes your DNS queries through a secure network of servers around the globe. The system uses threat intelligence from more than a dozen of the industry’s leading cybersecurity companies to give a real-time perspective on what websites are safe and what sites are known to include malware or other threats. If the system detects that the site you want to reach is known to be infected, you’ll automatically be blocked from entry – keeping your data and computer safe.

Why Quad9 provides security services

For the Internet to be an effective tool, users must trust their ability to use online services without fear of theft, fraud, or misuse of their devices by criminals. Public and private network operators need protection against malicious use of infrastructure resources and attacks against their users or customers. Quad9’s mission is to improve the security and stability of the Internet to allow everyone to be less vulnerable to risks and more effective in their daily online interactions.

Check to see if a domain is in the millions of malicious domains Quad9 blocks

Enter a hostname or domain name to check if it is blocked by Quad9


How to use Quad9

Quad9 can be used simply by setting the DNS server settings for your device to the addresses given in one of our service profiles. No sign-up is required, no account data needs to be given to Quad9, and there is no contract. Quad9 is free to use and collects no personal data about you. You can configure your router or wifi access point to distribute these settings, which will extend protection to all the elements on your local network including IoT devices, many of which otherwise would not have any anti-malware defenses.

Why participate?

Quad9 is a not-for-profit organization, relying on grants and partnerships with commercial and non-commercial sources and from individuals. Your use of Quad9 may prevent a ransomware attack, prevent your bank account from being compromised, or protect your laptop from being used as part of an illicit criminal attack on others. All of these potential protections and many millions of other interventions have a direct savings result for you, your business or organization, and the companies you rely on such as banks and e-commerce firms. We hope that this understanding may inspire you to donate to Quad9, as an individual or with a corporate sponsorship.

Donate ▸