CNAME Record Lookup — Check a Hostname’s Alias

What is a CNAME record?

A CNAME record makes one hostname an alias for another. When a resolver meets a CNAME it restarts the lookup at the target name and returns whatever that name holds. It is how a CDN, a SaaS product or a status page gets to live under your domain without you tracking its IP addresses.

Fields in a CNAME record

Field	Meaning
Name	The alias — the name that was queried.
TTL	Seconds a resolver may cache the alias.
Canonical name	The target the alias points to. Resolution continues from there.

How to read the results

A CNAME answer has exactly one target. If the target is itself a CNAME you have a chain, which works but costs an extra round trip per hop. Use the DNS Lookup with type A on the final target to see where the chain actually lands.

Rules worth knowing

A name with a CNAME cannot have any other record — no A, no MX, no TXT. This is a hard rule from RFC 1034, not a convention.
Because of that rule, you cannot put a CNAME at the zone apex (example.com): the apex must carry SOA and NS records. Providers work around this with non-standard "ALIAS" or "ANAME" records.
MX and NS records must not point at a CNAME. Their targets have to be names with real address records.
Chains are legal but each hop adds latency. Keep them short.
The target does not have to be in your zone — that is the whole point of the record.

Common problems

What you see	Usual cause
The DNS panel refuses the record	You are trying to add a CNAME to a name that already has other records, or to the apex. Both are disallowed.
Mail stopped working	A CNAME was added to a name that also needs MX records. The CNAME takes over the whole name and the MX records become unreachable.
No records	The name has no CNAME. It may hold A/AAAA records directly — look those up instead.
The alias resolves somewhere unexpected	You are following a chain. Query each target in turn to find the hop that changed.

Look up another record type

Each record type has its own page with the same explanation of its fields, or use the full DNS Lookup to query every common type at once.

A record AAAA record MX record TXT record NS record SOA record CAA record SRV record

Most often looked up alongside CNAME: A Record Lookup , AAAA Record Lookup , MX Record Lookup .

Data source: Public DNS-over-HTTPS resolvers. Queries go to the selected public resolver; results reflect that resolver’s cache. Learn about our data sources →

Frequently asked questions

Can I use a CNAME at the root of my domain?

Not in standard DNS. The apex must carry SOA and NS records, and a CNAME cannot coexist with other records. Many DNS providers offer an ALIAS or ANAME record that behaves like a CNAME at the apex by resolving it on their side.

What is the difference between a CNAME and an A record?

An A record holds an IP address; a CNAME holds another hostname. Use a CNAME when the target’s address is managed by someone else and may change.

Can a CNAME point to another CNAME?

Yes. Resolvers follow the chain, though every hop adds a lookup. Long chains are legal but slow, and some validators warn about them.

Why did adding a CNAME break my email?

A CNAME claims the entire name. Once example.com is a CNAME, its MX records are ignored, so inbound mail stops. Alias a subdomain instead.