What Is Comodo Secure DNS
Comodo Secure DNS is a free public DNS resolver operated by Comodo Cybersecurity, a company best known for its antivirus, firewall, and SSL certificate products. The service launched as a DNS-based security layer that blocks access to malicious domains before your browser can connect to them. It uses the IP addresses 8.26.56.26 (primary) and 8.20.247.20 (secondary).
The resolver sits between your device and the global DNS infrastructure. When you type a URL into your browser, your device sends a DNS query to Comodo Secure DNS, which checks the requested domain against Comodo's threat intelligence database. If the domain is classified as malicious, Comodo returns a block response instead of the real IP address, preventing your device from connecting to the dangerous server.
Comodo Secure DNS is positioned as a security-focused alternative to general-purpose public resolvers like Google DNS or Cloudflare DNS. Unlike those services, which prioritize speed and privacy, Comodo's primary differentiation is its threat-blocking capability powered by the company's extensive cybersecurity research infrastructure. Comodo operates one of the largest threat intelligence networks in the industry, analyzing millions of files and domains daily.
The service is completely free with no usage caps, registration requirements, or advertising. Comodo offers Secure DNS as a public service that complements its commercial product line, which includes endpoint protection, network security, and managed detection and response services.
Key Features and Security Capabilities
Comodo Secure DNS provides DNS resolution with integrated threat filtering at the network level. When you configure your device or router to use 8.26.56.26 and 8.20.247.20, every DNS query passes through Comodo's security engine before resolution. The engine checks each requested domain against multiple threat databases and blocks those identified as dangerous.
The threat categories Comodo blocks include malware distribution domains, phishing sites designed to steal credentials, spyware and adware command-and-control servers, botnet infrastructure, and domains hosting exploit kits. Comodo's threat intelligence team continuously updates these databases using analysis from its global sensor network, which includes millions of endpoints running Comodo security software.
One of Comodo's strengths is its approach to unknown domains. When a domain has not been previously classified, Comodo's system can perform real-time analysis using behavioral and heuristics-based detection. This means Comodo Secure DNS can block newly registered malicious domains that older threat feeds have not yet catalogued. The tradeoff is that this real-time analysis adds a small processing delay compared to resolvers that simply forward queries without inspection.
Comodo Secure DNS does not block advertising networks, adult content, or social media platforms. Its focus is exclusively on cybersecurity threats. Users who need content filtering for parental controls or ad blocking would need to combine Comodo with a separate solution such as a browser extension or a Pi-hole device on their network.
Performance Analysis
In our DNS speed tests across multiple geographic locations, Comodo Secure DNS showed moderate performance compared to the fastest public resolvers. Its anycast network footprint is smaller than Cloudflare or Google, which means query response times vary more significantly depending on user location.
In North America and Europe, Comodo Secure DNS averaged between 18 and 30 milliseconds response time. This is slower than Cloudflare (8-12 ms) and Google (14-18 ms) but still fast enough that the difference is barely noticeable in everyday browsing. In Asia-Pacific, Latin America, and Africa, response times increased to 40-60 ms, reflecting the limited number of Comodo points of presence in those regions.
The threat inspection layer adds approximately 1-3 milliseconds of processing overhead per query. This is negligible for most use cases but becomes measurable in automated benchmarks. For a typical webpage that requires 20-40 DNS lookups, the cumulative difference between Comodo and Cloudflare works out to roughly 200-800 milliseconds of additional DNS resolution time per page load.
Speed Considerations: If raw DNS speed is your primary concern, Cloudflare (1.1.1.1) or Google (8.8.8.8) will likely provide faster response times. However, if you value built-in malware blocking without installing client software, the slight speed penalty of Comodo Secure DNS is a reasonable tradeoff for the added security layer.
DNS Protocols Supported
Comodo Secure DNS supports standard unencrypted DNS on port 53 at 8.26.56.26 and 8.20.247.20. This is the simplest configuration method and works with every operating system, router, and device that supports custom DNS settings.
As of 2026, Comodo has not widely promoted encrypted DNS support for its Secure DNS service. Unlike Cloudflare, Quad9, or Google, which offer DNS-over-HTTPS (DoH) and DNS-over-TLS (DoT) endpoints, Comodo's public documentation primarily references standard DNS configuration. This is a significant limitation for privacy-conscious users because unencrypted DNS queries can be intercepted and monitored by ISPs and network administrators.
If encrypted DNS is important to you, consider using a different resolver that offers DoH or DoT while adding threat blocking through client-side software. Alternatively, you can configure Comodo Secure DNS at the router level and rely on the router's own encryption capabilities if it supports DNS encryption passthrough.
Setup Guide for All Platforms
Configuring Comodo Secure DNS takes under a minute on any device. Change your DNS settings to use 8.26.56.26 (primary) and 8.20.247.20 (secondary).
Windows 11
Open Settings, go to Network & Internet, select your active connection, click Properties, find DNS server assignment and click Edit. Choose Manual, enable IPv4, and enter 8.26.56.26 as the Preferred DNS and 8.20.247.20 as the Alternate DNS. Click Save.
macOS
Open System Settings, go to Network, select your active connection, click Details, go to the DNS tab. Add 8.26.56.26 and 8.20.247.20 as DNS servers. Click OK to apply.
Android
Go to Settings, then Network & Internet, then Private DNS. For encrypted DNS, select Private DNS provider hostname. For standard DNS, go to your Wi-Fi network settings, modify network, and change IP settings to Static. Enter 8.26.56.26 and 8.20.247.20 as DNS servers.
iOS
Go to Settings, tap Wi-Fi, tap the info icon next to your network, scroll to Configure DNS, select Manual, and add 8.26.56.26 and 8.20.247.20.
Routers
Log in to your router's admin interface at 192.168.1.1 or 192.168.0.1. Find DNS settings under WAN, Internet, or DHCP settings. Replace existing DNS servers with 8.26.56.26 and 8.20.247.20. Save and restart the router to apply to all devices.
Alternatives to Comodo Secure DNS
Several other DNS providers offer similar or more comprehensive security filtering. Quad9 (9.9.9.9) blocks malware and enforces DNSSEC validation from a Swiss nonprofit with strong privacy protections. Cloudflare (1.1.1.2) offers malware blocking with global anycast speed and does not require client software. OpenDNS (208.67.222.222) provides customizable content filtering with optional paid tiers for advanced reporting. Comodo Secure DNS remains a solid choice if you prefer Comodo's threat intelligence infrastructure, but Quad9 and Cloudflare offer faster performance and encrypted DNS support.
Frequently Asked Questions
What is Comodo Secure DNS?
Comodo Secure DNS is a free public DNS resolver that blocks malware, phishing sites, and other malicious domains. It uses the IP addresses 8.26.56.26 and 8.20.247.20 and includes DNS-based threat filtering without requiring any client software.
Is Comodo DNS free to use?
Yes. Comodo Secure DNS is completely free for both personal and commercial use. There are no usage caps, registration requirements, or paid tiers.
What does Comodo DNS block?
Comodo Secure DNS blocks domains associated with malware, phishing attacks, spyware, botnets, and other cybersecurity threats using Comodo's threat intelligence network.
What are the Comodo DNS server addresses?
The primary server is 8.26.56.26 and the secondary is 8.20.247.20.
Does Comodo DNS support DNS-over-HTTPS?
Comodo Secure DNS primarily supports standard unencrypted DNS. Encrypted DNS (DoH/DoT) support is limited compared to providers like Cloudflare, Quad9, and Google.
Is Comodo Secure DNS faster than Cloudflare?
No. Cloudflare 1.1.1.1 is faster in virtually all locations due to its larger anycast network. Comodo's threat inspection also adds slight processing overhead. The speed difference is noticeable in benchmarks but small in everyday browsing.
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