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Network

DNS Lookup

Query DNS records by type for a host.

Formula reviewed: 2026-02-14 Network

DNS Lookup queries live DNS records for a hostname and selected record type. DNS resolution is a distributed lookup process in which recursive resolvers ask authoritative nameservers for records such as A, AAAA, CNAME, MX, TXT, NS, or CAA. Different record types answer different operational questions: address records route web traffic, MX records route mail, TXT records often prove ownership or define email policy, and NS records identify the authoritative servers for a zone. Results can differ by resolver because of caching, TTL, split-horizon DNS, or recent changes. This tool is useful for troubleshooting and documentation, but authoritative nameserver checks are best when confirming production truth.

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Input Pattern

Enter values in the left panel, keep units explicit, run the calculation, then copy or share the result. Invalid fields are highlighted immediately.

How to use this tool

  1. Enter the hostname you want to check, such as example.com or mail.example.com.
  2. Choose the record type: A, AAAA, CNAME, MX, TXT, NS, CAA, or another supported type.
  3. Run the lookup and review returned values, errors, or empty answers.
  4. Compare recursive lookup results with your DNS provider or authoritative nameserver before making a production change.

DNS Lookup

Result

Enter a host like example.com, then choose the record type you want to query.

Formula or method

Worked example

Checking email DNS before a cutover

Result: The lookup returns the mail exchanger hostnames visible to the resolver.

If the expected mail host is missing, check authoritative DNS, TTL, provider settings, and whether old records are still cached.

How to interpret the result

DNS answers are resolver-visible facts at a point in time. Use them to narrow the failure mode, then verify authoritative nameserver data before production changes.

Common mistakes

Formula References

Assumptions

Review note and limitations

Method - live DNS resolver lookup; results depend on resolver behavior, TTL, caching, and current network conditions.

Diagnostic aid only. Confirm production DNS with authoritative nameservers, provider settings, and current resolver behavior.

FAQ

What DNS record type should I check first?

For web traffic, start with A and AAAA records. For email delivery, start with MX and TXT records. For delegation, check NS records.

Why do DNS lookup results differ between tools?

Different tools may query different recursive resolvers, and each resolver can have different cached answers until TTLs expire.

Does this show authoritative DNS?

It shows the answer available through the lookup path used by the tool. For authoritative truth, compare with your DNS provider or authoritative nameserver.

Explore more versions

Tailored guides for specific audiences, regions, and scenarios.

Related tools and workflows

DNS issues often involve propagation, WHOIS, IP ownership, SSL, and HTTP headers, so related tools help check the surrounding domain stack.