DNS lookup
Type a domain name and choose a record type to see what public DNS answers, including the TTL (how long the answer may be cached). Choose ALL to see the main record types at once. The query goes to a public resolver, so you see what the rest of the internet sees. The name you type is sent to our server only to make the query.
Which record should you check?
- A and AAAA
- The IPv4 and IPv6 addresses a name points to. Start here when a site does not load.
- CNAME
- Makes a name an alias of another one. A name with a CNAME has no A record of its own: the address belongs to the target.
- MX
- The servers that receive the domain’s email, in order of priority.
- NS and SOA
- NS lists the name servers that hold the domain’s records; SOA holds administrative data such as the serial number and refresh times.
- TXT
- Free text, used for SPF, domain verification and many other things.
- SPF
- Lists the servers allowed to send email for the domain. A domain should have only one SPF record: a TXT record that starts with v=spf1.
- DMARC
- Tells receivers what to do with email that fails SPF and DKIM (nothing, quarantine or reject) and where to send reports. It is a TXT record at _dmarc.<domain>.
- DKIM
- A cryptographic signature added to every message. The public key is published as a TXT record at <selector>._domainkey.<domain>, so you need the selector your email provider uses.
- PTR
- The reverse of an A record: the name an IP address maps to. Mail servers often check it.
- SRV
- Where a service runs: the server, the port, the priority and the weight. The name has the form _service._protocol.domain.
- CAA
- Which certificate authorities may issue certificates for the domain.
Questions
What is a DNS record?
An entry in the DNS that says something about a name: which IP address it points to (A and AAAA), where its email goes (MX), which servers are authoritative (NS), or free text such as SPF or verification codes (TXT).
What is the TTL?
Time to live: the number of seconds that resolvers may keep the answer before asking again. A low TTL means a change reaches everyone sooner; a high one means fewer queries but slower changes.
What does “No records found” mean?
The name exists, but it has no record of the type you asked for. That is normal: a domain used only for email may have no A record, and many domains have no AAAA.
What does NXDOMAIN mean?
The domain name does not exist at all. Check for a typo, or whether the domain expired or was never registered.
What does SERVFAIL mean?
The resolver could not get a valid answer: the domain’s name servers did not respond, returned an error, or the DNSSEC signature does not validate. It is usually a problem with the domain’s DNS setup, not with your connection.
Why does ALL not use the ANY query?
Many servers refuse or truncate ANY queries (RFC 8482), so the result would be incomplete and inconsistent. ALL instead asks for each main type separately: A, AAAA, CNAME, MX, NS, SOA, TXT and CAA.
What is the difference between authoritative and recursive answers?
An authoritative server holds the domain’s records and is the source of truth. A recursive resolver, like the one this tool uses, asks the authoritative servers for you and may serve a cached answer until the TTL runs out. After a change, the two can differ for a while.
I see a CNAME but no IP address. Why?
A CNAME makes the name an alias of another name, and the IP addresses belong to that target. Look up the A or AAAA record of the target, or choose ALL on the target name.