Free tool

Free nameserver lookup

Nameserver Lookup

Free, no sign-up. We only fetch the public URL you enter.

Short answer

Enter a domain such as example.com above and the nameserver lookup queries DNS for its NS records. The result lists each authoritative nameserver – for example ns1.dnsprovider.example – and the TTL in seconds. Those servers are where your A, AAAA, CNAME, MX and TXT records live, so changes only count if you make them at that provider. Nameserver switches can take 24–48 hours to settle because of caching at several levels. monitordefend’s uptime check, running every five minutes, emails you if a DNS mix-up takes your site offline.

  • Free, no sign-up: all NS records of a domain with TTL.
  • NS records show where your DNS is hosted – edit records only there.
  • Use at least two nameservers, ideally on separate networks.
Nameserver lookup · example result
myshop.com · NS
myshop.com.  86400  IN  NS  ns1.dnsprovider.example.
myshop.com.  86400  IN  NS  ns2.dnsprovider.example.
myshop.com.  86400  IN  NS  ns3.dnsprovider.example.
Three authoritative nameservers at one DNS provider – a typical, redundant setup.

This free nameserver lookup shows which servers are authoritative for a domain – in other words, which DNS provider actually answers for it. Enter a domain and you get its NS records with their TTL. When DNS edits seem to have no effect, when a site or mailbox points to the wrong provider, or right after you moved DNS to a new host, the NS records are the first thing to check, because every other record depends on them.

How does the nameserver lookup work?

You enter a domain and run the check. The tool sends a DNS query of type NS for that name and prints each nameserver it receives together with the TTL. Normally you look up the registered domain itself – example.com, not www.example.com – because that is where the delegation lives. Subdomains only return their own NS records if they have been delegated to separate nameservers.

The answer shows the nameservers as published in DNS. If you changed them a few minutes ago, a resolver may still serve the old list from its cache, so compare the result with what your registrar shows and allow for the TTL.

What are nameservers (NS records)?

NS records tell the internet which nameservers are authoritative for your domain: which servers hold the zone and answer questions about it. When a resolver wants the A record of www.example.com, it first learns from the .com servers which nameservers are responsible for example.com, then asks those servers directly.

. (root zone)
  • .com TLD serversKnow the delegation of myshop.com
  • NS myshop.com → ns1/ns2.dnsprovider.exampleSet at the registrar
  • ns1.dnsprovider.exampleAuthoritative for the zone
  • A, AAAA, MX, TXT, CNAME …The actual records
Delegation runs from the root via the TLD to your nameservers, which hold the real records.

The nameservers therefore define where your DNS zone is hosted and which provider is responsible for answering queries for every other record type – A, AAAA, CNAME, MX, TXT and the rest. Change them, and you hand the whole domain to a different provider in one step. That is why NS changes are the most powerful and the most dangerous edit you can make to a domain.

When should you check nameservers?

Nameserver questions usually show up disguised as something else: an edit that “doesn’t save”, email that goes to an old provider, a website that still shows last year’s version. Checking NS first saves you from debugging the wrong panel.

Nameservers vs DNS records

The distinction is simple but constantly mixed up. Nameservers (NS) say where your DNS is hosted – who answers queries. Records such as A, CNAME, MX and TXT are the actual instructions inside that zone. A domain can have perfectly correct records at one provider and still not work, because its nameservers point at another provider whose zone is empty or outdated.

Nameservers vs DNS records
Nameservers (NS)
Where DNS is hosted – who answers queries
A / AAAA
Which IP the website lives on
CNAME
Which name a subdomain is an alias of
MX / TXT
Mail servers, SPF, verification
NS decides the provider; the other records are the instructions inside its zone.

Your registrar (where you bought the domain) and your DNS provider (who runs the nameservers) can be the same company or two different ones. The registrar stores which nameservers the domain uses; the DNS provider stores the records. If you are not sure who your DNS provider is, the hostnames in the NS result usually give it away.

Why WHOIS and NS lookup results can differ

WHOIS or RDAP shows the nameservers registered at the registrar and the TLD registry – the delegation. An NS lookup asks DNS, and the answer can come from the zone itself at the authoritative servers. Normally both lists match.

They can disagree during a change, when one side has updated and caches still hold the other, or when they were configured inconsistently: the registrar delegates to ns1 and ns2, but the zone at the provider lists ns1, ns2 and an old ns3. Resolvers mostly follow the delegation, but inconsistent lists invite odd, intermittent failures. Keep the NS records in your zone identical to what the registrar has.

Glue records

Glue records are IP addresses for nameservers that the registry stores alongside the delegation. They are needed when a nameserver lives inside the domain it serves – for example ns1.example.com for example.com. Without glue, a resolver would need to ask example.com’s nameservers for the address of example.com’s nameserver, a circular lookup that never finishes.

If you use your DNS provider’s nameservers under its own domain, you never need glue; the provider handles it. If you run your own “vanity” nameservers, register the glue at your registrar and keep it updated whenever those servers change IP – stale glue is a classic cause of a domain that suddenly stops resolving.

How long do nameserver changes take to propagate?

Delegation changes typically take anywhere from a few minutes up to 24–48 hours to be seen everywhere. The registry usually publishes the new delegation quickly, but resolvers that cached the old NS records keep using them until the TTL – often a full day for NS – runs out. Some resolvers also cache the old provider’s answers for individual records.

A nameserver switch, step by step
  1. All records recreated at the new DNS provider
  2. Nameservers changed at the registrar
  3. TLD servers delegate to the new provider
  4. Old NS answers expire from resolver caches
  5. Old provider’s zone safe to delete
Copy the zone first, switch second, and keep the old zone until caches have expired.

Plan for that window. Recreate every record at the new provider before you switch, compare the two zones, then change the nameservers at the registrar. Leave the old zone untouched for a few days, so visitors whose resolvers still ask the old provider get correct answers, and only then delete it.

I changed nameservers – why is my site or email still using the old DNS?

Most often it is caching: some resolvers have not expired the old delegation yet. A lookup that already shows the new nameservers confirms the change itself went through; waiting is then the only fix.

The second common cause is editing records at a provider that is not authoritative – the old one, or a second account. If the NS result names provider B, edits at provider A have no effect. And if email still fails after the switch, check that the MX, SPF and DKIM records were really copied to the new zone; they are the ones most often forgotten.

How many nameservers should a domain have?

At least two – most registries require that – and most providers hand out two to four. Redundancy is the point: if one server or its network fails, resolvers try the next one and the domain keeps resolving. For extra resilience, the servers should sit on separate networks; large providers use anycast so each nameserver name is served from many locations.

Nameservers and monitordefend

monitordefend does not monitor NS records or DNS delegation. If a nameserver mistake makes your website unreachable, its uptime check notices within minutes, confirms the outage with a second attempt and sends you an email.

Frequently asked questions

What is a nameserver (NS record)?

Nameservers are the DNS servers that are authoritative for your domain – where the real records such as A, MX, CNAME and TXT live. NS records list them.

How do I find out which DNS provider is authoritative for my domain?

Run a nameserver lookup. The NS results are the servers the internet uses to answer DNS queries for your domain, and their hostnames usually reveal the provider.

Why do WHOIS nameservers and NS lookup results sometimes differ?

WHOIS shows what is set at the registrar and TLD level, while an NS lookup queries DNS. During changes, or when the zone lists different servers than the registrar, they can temporarily disagree.

How long do nameserver changes take to propagate?

Typically up to 24–48 hours, depending on caching and the TTLs at the TLD and in resolvers. Many resolvers pick up the change much sooner.

What are glue records, and when do I need them?

Glue records are IP addresses for nameservers stored at the registry. You need them when the nameserver is under the same domain it serves, such as ns1.example.com for example.com.

I changed nameservers – why is my website or email still using the old DNS?

Usually caching, or you are editing records at a provider that is not the authoritative one listed in your NS results. Also check that all records were copied to the new zone.

How many nameservers should a domain have?

Two or more, so DNS keeps working if one server goes down. Placing them on different networks adds further resilience.

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