CNAME Chain Tracer
Trace a domain’s CNAME alias chain to where it finally points.
The domain to look up
How this lookup works
A CNAME record makes one name an alias for another, so www.example.com can point at your CDN or hosting provider’s hostname. This tool queries the record and shows where the alias leads.
What the results mean
- CNAME target
- The hostname this name is an alias for. Everything else — the address, the mail servers — is then looked up on that target instead.
- No CNAME record
- Normal. Root domains cannot have a CNAME, and many names simply point straight at an address instead. It is not an error.
Common problems and fixes
- The chain goes through several hostnames before ending
- That is normal for platform hosting — your name points at the provider, whose name points at their load balancer, whose name resolves to addresses. Each hop is a lookup, so a long chain adds latency to a first connection, but it is what lets the provider move infrastructure without you touching anything.
- Adding a CNAME broke email for the subdomain
- A CNAME cannot coexist with any other record on the same name, so it takes precedence over the MX, TXT and A records you thought were there. That is the specification working as designed. Anything needing its own MX or TXT records has to be an A record rather than an alias.
- The alias still points at the old target
- Caching, at whichever step of the chain you changed. Every name in a CNAME chain is cached separately with its own TTL, so altering one link leaves the others serving old answers until each expires — which is why a chain can appear half-updated. Lowering TTLs a day before a planned move is the fix; afterwards there is only waiting.
Frequently asked questions
Why can’t my root domain have a CNAME?
A CNAME cannot coexist with other records, and a root domain must carry NS and usually MX records. That is why providers offer workarounds like ALIAS or ANAME records for the root, which behave like a CNAME but resolve differently.
What is a CNAME used for?
Pointing a subdomain at a service you do not control the address of — a CDN, a hosting platform, a status page. When their address changes, your CNAME follows automatically because it points at their name, not their number.
Is a CNAME slower than an A record?
Marginally, and only on a cold cache. Each alias in the chain is an extra lookup before an address is known, which costs a few milliseconds on the first request and nothing afterwards, since resolvers cache each step. The operational benefit of not hardcoding somebody else's IP address is worth considerably more than that.
What is the difference between ALIAS, ANAME and CNAME flattening?
All three are provider-specific answers to the same problem: a root domain cannot hold a CNAME. The nameserver resolves the target itself and returns the resulting address as though it were an A record, so the standard is respected while you still get the indirection. The names differ by provider; the behaviour is essentially the same.
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