What this tool does
DNS (the Domain Name System) translates human-readable domain names into the information servers and software actually use: IP addresses, mail servers, authoritative name servers, and arbitrary verification text. This tool queries a domain's public DNS records directly — A, AAAA, MX, TXT, and NS — and shows them exactly as returned, with no interpretation or security scoring: it's a diagnostic tool, not a vulnerability scanner.
Why check your DNS records
DNS configuration breaks silently more often than people expect: an MX record misspelled after switching email providers, an A record still pointing at an old server after a hosting migration, or a verification TXT record accidentally wiped during a zone cleanup. Each produces a different symptom — mail stops arriving, the site shows an old version, access to a third-party tool disappears — with no explicit error message. The only way to confirm any of it is to look directly at what DNS is actually returning.
A and AAAA records: where your site actually lives
These two record types point to the IP address that actually answers requests for the domain. After a hosting migration, it's common for one to get updated and not the other — a domain with a fresh A record but a stale, outdated AAAA record will serve a different version of the site depending on whether the visitor connects over IPv4 or IPv6, which explains some "works on my machine" bugs that seem inexplicable until you check the DNS.
MX and TXT: mail delivery and ownership verification
MX records determine which server receives email sent to the domain, ranked by priority (lower numbers go first). TXT records have no fixed format — they're used just as often to publish an anti-spoofing SPF policy as to prove domain ownership to a third-party service (Google, Microsoft, and so on). A domain can legitimately accumulate dozens of these over the years as more tools get connected to it; that's not a sign of misconfiguration by itself.
NS: who's actually authoritative
NS records show which name servers are authoritative for the domain — in other words, who gets asked first for everything else. Changing registrars or DNS providers updates these records before anything else changes; if they don't match the DNS provider you think you're using, that's often a sign of an incomplete migration or an old registrar still answering.