DNS over HTTPS (DoH) encrypts DNS queries using HTTPS, preventing eavesdropping and manipulation of DNS traffic. Our DoH Checker resolves DNS records through multiple providers — Cloudflare, Google, and Quad9 — so you can compare responses and verify DoH availability. This is essential for privacy-conscious users and organizations enforcing encrypted DNS policies.
How to Use
1Enter the domain name you want to resolve via DoH.
2Select the DNS record type (A, AAAA, MX, TXT, CNAME, or NS).
3Click "Check" to resolve the record through all DoH providers and compare results.
Use Cases
•Verify DNS records are consistent across multiple DoH providers
•Test if DNS resolution works over HTTPS for privacy auditing
•Troubleshoot DNS propagation issues using encrypted queries
•Compare response times between different DoH endpoints
•Validate DNSSEC-signed records via authenticated DoH providers
Frequently Asked Questions
DoH is a protocol that sends DNS queries over HTTPS encryption, preventing ISPs and network observers from seeing or modifying your DNS traffic. It improves privacy and security compared to traditional plain-text DNS.
Cloudflare at 1.1.1.1, Google DNS at 8.8.8.8 and Quad9 at 9.9.9.9, the three best-known public resolvers that offer DNS over HTTPS. Comparing them is genuinely informative rather than redundant: they differ in filtering, in how aggressively they cache, and in edge reach, so a discrepancy between two of them points at something real, such as a record one of them has cached and the other has not yet refreshed, or a filtering policy applied by one.
DoH can be slightly slower due to TLS overhead, but modern implementations use connection reuse and HTTP/2 to minimize latency. Many users find the privacy benefits worth the small performance trade-off.
It closes two gaps in ordinary DNS. Encryption means an on-path observer cannot read which names are being looked up, which is a substantial privacy leak since the domain list often reveals what a user is doing. Authentication means a responder cannot be substituted, so tampering with answers — the basis of several real attacks — stops working. Neither replaces TLS for the traffic itself.
Most often caching: one resolver has a stale answer while another has already refreshed. Filtering is the other common cause — some resolvers block domains they classify as malicious or advertising, returning a different address or nothing at all. Split-horizon answers and regional load balancing produce legitimate differences too. The comparison is only interesting when you know which causes are plausible for your domain.
Often yes, and without you necessarily noticing. Chrome, Firefox and Edge have shipped encrypted DNS by default in recent versions, and some operating systems offer it system-wide. That means your resolver queries may already be encrypted even if you never configured anything, and the effective resolver may be the browser's rather than your ISP's. You can confirm in the browser's own security or privacy settings.
For an organisation, often yes — it centralises logging, filtering and caching while keeping queries off the public resolvers your users would otherwise reach. The trade-offs are that you become responsible for availability and for the privacy of the queries you can now see, and that client support varies. For an individual, the built-in browser option is usually the better balance of effort against benefit.
No. It hides the contents of queries from anyone on the network path, and authenticates the responder. It does not hide the fact that a connection to a resolver happened, and resolvers themselves still see everything. Encrypted client hello can conceal more of the connection's metadata, and both together cover considerably more ground than DoH alone — which matters if your threat model includes an observer counting lookups rather than reading them.
How the Providers Are Queried
The point of DNS over HTTPS is that the lookup itself is encrypted and authenticated. This page queries several public resolvers that way and reports each answer independently.
1Send the same question to each provider using the JSON API they share, requesting a JSON-formatted answer. That format is what makes the result machine-readable rather than something to parse out of a web page.
2Filter the response by the record type asked for, converting the name to the numeric type code the wire format uses. Without that filter a query for A records can return the CNAMEs and intermediates that led to the answer.
3Report per provider, including failures. A provider that returns an error is reported with that error rather than omitted, because a resolver that cannot be reached is a different fact from one that returned nothing.
Comparing providers is the practical use: disagreement points at cache state or filtering, and agreement across independent encrypted resolvers is good evidence the answer is what the domain really publishes.
Tips & Best Practices
•Use DNS over HTTPS to encrypt DNS queries for privacy
•Verify DoH server certificates for trust and validity
•Test DoH connectivity from different networks and locations
•Monitor DoH server availability and response times
Technical Details
Protocol: DNS over HTTPS (DoH) support detection Server: DoH server certificate and connection analysis Privacy: DNS query encryption and privacy verification Output: DoH support status with server recommendations
