DNS Lookup
Look up A, AAAA, MX, TXT, NS, CNAME, SOA, and CAA records for any domain.
Written by Anil Gautam · Updated
How do you read MX, TXT, SOA and CAA records?
Each result row shows the record type, its TTL in seconds and the record data, with a Copy button for that row. MX data starts with a priority number, and lower numbers are tried first. Look up MX for gmail.com and you get five records with priorities 5, 10, 20, 30 and 40, so mail goes first to gmail-smtp-in.l.google.com, the host with priority 5. Rows can arrive in any order, and only the priority number decides which server comes first.
TXT records hold text that mail servers and other services read. An SPF policy begins with v=spf1 and sits on the domain itself. DMARC lives on a separate name, so look up TXT for _dmarc.example.com, and DKIM keys sit under a selector, as in selector._domainkey.example.com, where the selector comes from your mail provider. CAA records list the certificate authorities allowed to issue certificates for the domain, for example 0 issue "letsencrypt.org".
An SOA record has seven fields in a fixed order: the primary nameserver, the administrator's mailbox written with a dot in place of the @, the zone's serial number, the refresh, retry and expire times for secondary servers, and the time resolvers may cache a "no such record" answer. A record ending 7200 3600 1209600 3600 means 2 hours, 1 hour, 14 days and 1 hour.
What does an empty result or a DNS status code mean?
The status line above the records shows OK (NOERROR) when the query succeeded and a numeric code otherwise. Code 3 is NXDOMAIN: the name itself does not exist, often because of a typo or an expired domain. SERVFAIL, code 2, means the resolver could not get a usable answer, which commonly comes from broken DNSSEC signatures or unreachable nameservers.
NOERROR with zero records means the name exists but has nothing of that type, for example a domain without IPv6 returning no AAAA records. In that case the Authority section below usually shows the zone's SOA record. CNAME lookups on a bare domain normally come back empty, because a CNAME cannot sit beside the SOA and NS records at the top of a zone, so try the www name instead.
Where does the lookup run?
Your browser sends the domain and record type to the OneClickUse server, which passes them to a separate lookup service, so the answers reflect public DNS as the rest of the internet sees it. Names that exist only on an office network's internal DNS, or in your computer's hosts file, will not appear. To find who registered a domain and when it expires, use the WHOIS / RDAP Lookup, and to see who runs the address in an A record, paste it into the IP Lookup.