Skip to main content
HostTracker
HOST-TRACKER
website monitoring service
Status pages Instant check Price
Login Register

CNAME lookup: see where a hostname points

Enter a hostname such as www.example.com to see its CNAME record - the name it is an alias for - as public DNS resolvers in several countries return it.

Examples: 300+ locations worldwide · results in about 10 seconds

You've used today's free checks

Create a free account to keep checking. It takes less than a minute, and new free checks are available again tomorrow.

Start 30-day free trial Already have an account? Log in
{{error.message}}

Unlock the full report

30-day free trial · cancel anytime

Loading plans…
See all plans & pricing
Recommended
{{ plan.name }}
{{ money(priceMo(plan)) }}/mo
  • {{ plan.maxTaskCount == null ? 'Unlimited' : plan.maxTaskCount }} monitored sites
  • All check locations in the report
  • TLS, headers & timing details
  • Scheduled reports
  • REST API access
Start free trial
Billed only after your trial · Compare all plans

What a CNAME lookup shows

The canonical name a hostname is an alias for, as public DNS resolvers in several countries return it, with every location's own answer underneath.

Find out more

Why the answer can differ by location

Resolvers cache a CNAME for its TTL, so right after a change some locations still return the old target. Some DNS providers also answer by region on purpose.

Find out more

A broken alias looks like a site that is down

When a CNAME points at the wrong place, visitors see an error page or someone else's content. Website monitoring catches that from the outside.

Find out more

Need other record types? The DNS lookup shows A, AAAA, MX and TXT records, and the TXT record lookup lists every TXT string of a name.

Key takeaways

  • This tool queries the CNAME (canonical name) record of the hostname you enter from several HostTracker locations, asking five public DNS resolvers at each one.
  • It lists each target the alias points to with the countries that returned it, and every location's own answer, including locations where no CNAME came back.
  • A CNAME lookup returns one step of an alias chain; each target can be looked up in turn with one click.
  • A root domain such as example.com cannot carry a CNAME record, so a lookup there normally finds none.
  • It is free, needs no login and no credit card.

Frequently asked questions.

A CNAME (canonical name) record makes one hostname an alias of another. When a resolver looks up www.example.com and finds a CNAME pointing to example.net, it continues with example.net and returns that name's addresses. It is how a subdomain is pointed at a hosting platform, a content delivery network or another hosted service without copying its IP addresses, which can then change without any edit on your side.
Enter the exact hostname, such as www.example.com or shop.example.com, and run the lookup. The "Points to" column shows the canonical name the resolvers returned, with the countries that returned it. From a terminal, dig CNAME www.example.com +short on macOS or Linux, or nslookup -type=cname www.example.com on Windows, asks your own resolver the same question.
Usually because the name is not an alias: it has A or AAAA records of its own, which the DNS lookup shows. Other common causes: the CNAME was added on a different name (www.example.com and example.com are separate names), it was saved at a DNS provider the domain does not use, or the name does not exist at all. A record created a few minutes ago can also still be hidden behind a cached "no such record" answer, which resolvers keep for a time set in the zone's SOA record (RFC 2308).
No. A CNAME cannot share its name with any other record (RFC 1034 and RFC 2181), and the root of a zone always carries SOA and NS records. Some DNS providers offer an ALIAS, ANAME or "CNAME flattening" record for the root instead: the provider resolves the target itself and answers with A and AAAA records, so a CNAME lookup on the root domain still shows no CNAME.
It shows one step: the canonical name the record points to. A resolver answers a CNAME query with the record at that exact name and stops there. If the target is an alias too, the "Look up this name" link next to it runs the next step; repeat until a lookup shows no CNAME, which means you have reached a name with addresses of its own. Keep chains short, because every extra step is one more lookup before a browser can connect.
No. The target of a CNAME must be a hostname. To point a name at an IP address, use an A record for IPv4 or an AAAA record for IPv6. If you need to know which network an address belongs to, the subnet calculator works out its range.
No. A name with a CNAME may hold no other records, so most DNS providers refuse to add an MX record or a TXT verification string next to it, and where one slips through, resolvers handle the conflict inconsistently. Put those records on a name that is not an alias, or replace the CNAME with A and AAAA records.
Up to the old record's TTL (time to live), because resolvers keep serving their cached answer until it expires: with a TTL of 3,600 seconds that is up to an hour. Locations that still show the previous target are resolvers whose cache has not run out yet, so run the lookup again after the TTL. HostTracker checkpoints keep each answer for at least 3 minutes as well. The DNS propagation guide explains the timing in detail.
Most often a change is still spreading: some resolvers have refreshed and others still hold the old target. Some DNS providers also answer differently by region on purpose, sending visitors to the nearest servers of a content delivery network, and then every target can be correct at the same time. Compare the targets with the record at your DNS provider; if yours is there and the old one only appears in a few locations, wait for the TTL.
Yes. It needs no signup and no credit card. Each lookup is one instant check, and at every location it runs from it asks five public DNS resolvers.

Part of HostTracker's website monitoring software.