Cloudflare and Quad9, two of the most popular upstream DNS providers for Pi-hole, offer distinct advantages, but the most surprising truth is how little actual performance difference you’ll notice for typical home use, despite their vastly different philosophies.
Let’s see this in action. Imagine a user, "Alice," running a Pi-hole on her home network. She’s curious about the differences between Cloudflare (1.1.1.1) and Quad9 (9.9.9.9) as her upstream DNS servers.
First, Alice configures her Pi-hole. She logs into her Pi-hole web interface, navigates to Settings > DNS, and under "Upstream DNS Servers," she enters:
For Cloudflare:
1.1.1.1
1.0.0.1
For Quad9:
9.9.9.9
149.112.112.112
She then clicks "Save" and restarts the Pi-hole DNS service.
Now, Alice wants to test. She opens a terminal on a client machine connected to her Pi-hole network and runs a few DNS lookups using dig:
dig google.com @127.0.0.1
dig amazon.com @127.0.0.1
dig wikipedia.org @127.0.0.1
The output for each will show the IP address for the requested domain. If Alice were to time these queries (using time dig ...), she’d likely find millisecond-level differences, often negligible. The real divergence lies in their underlying principles and what they promise to deliver besides just speed.
Cloudflare DNS (1.1.1.1) focuses on speed and privacy. They have a massive global network of Anycast servers, designed to resolve DNS queries as quickly as possible by routing them to the geographically closest server. Their privacy stance is strong: they claim not to log personally identifiable information from DNS queries and to delete logs after 24 hours. They also offer DoH (DNS over HTTPS) and DoT (DNS over TLS) at the upstream level, though Pi-hole typically uses plain DNS unless specifically configured for encrypted upstream.
Quad9 DNS (9.9.9.9), on the other hand, prioritizes security. Their core offering is a free, recursive, anycast DNS platform that blocks malicious domains. They partner with various threat intelligence providers to maintain a real-time blocklist of known phishing, malware, and command-and-control servers. When a query matches a domain on their blocklist, Quad9 simply returns an NXDOMAIN (non-existent domain) response, preventing your device from connecting to the harmful site. While they also value privacy and don’t sell user data, their primary differentiator is this active threat blocking.
So, how does Pi-hole leverage these? Pi-hole acts as your local DNS resolver. When a device on your network asks Pi-hole for an IP address, Pi-hole first checks its local blocklists. If the domain isn’t blocked locally, Pi-hole then forwards the request to one of its configured upstream DNS servers (Cloudflare or Quad9 in this case). The upstream server resolves the domain and sends the IP address back to Pi-hole, which then forwards it to the original client. Pi-hole’s own blocking is the first line of defense, and the upstream is the second.
The levers you control with Pi-hole are straightforward:
- Upstream DNS Servers: This is where you choose your provider(s) (e.g.,
1.1.1.1,9.9.9.9, or even custom ones). - Blocklists: These are the lists Pi-hole downloads and uses to perform its own local blocking.
- Conditional Forwarding: This allows Pi-hole to ask your router for local network names, which is useful for identifying devices by hostname in Pi-hole’s query logs.
- DNSSEC: You can enable DNSSEC validation in Pi-hole’s settings, which adds another layer of security by verifying the authenticity of DNS responses. Both Cloudflare and Quad9 support DNSSEC.
The one thing most people don’t realize is that Pi-hole’s own ad-blocking power far eclipses the performance or security differences between major upstream providers for typical home users. If a domain is on a Pi-hole blocklist, it’s blocked before it even hits Cloudflare or Quad9. The speed difference between these two is also often measured in single-digit milliseconds, which is usually imperceptible compared to the latency of fetching web page content itself. Therefore, the choice between Cloudflare and Quad9 for Pi-hole becomes less about raw speed and more about whether you want the upstream provider to handle additional security filtering (Quad9) or if you prefer a purely speed- and privacy-focused upstream with Pi-hole handling all the blocking (Cloudflare).
Once you’ve settled on an upstream DNS provider and are comfortable with Pi-hole’s blocking, the next logical step is to explore Pi-hole’s ad lists and how to manage them, or to investigate setting up Pi-hole for DNS-over-HTTPS (DoH) with your chosen upstream.