WHOISNS Lookup
Find the authoritative nameservers for any domain.
What is an NS lookup?
An NS lookup finds the nameservers for a domain: the servers that hold its DNS zone and give the official answer for every other record, from the website's address to its mail servers. If the nameservers are wrong or not responding, nothing else in the domain's DNS can be found, so this is often the first check when a site or email suddenly stops working.
This tool lists each nameserver, resolves it to an IPv4 address and shows the TTL of the NS record.
How NS records work
Nameservers are set in two places. The registrar sends them to the registry for the domain's extension, which publishes them as a delegation: the signpost that tells resolvers where to go. The DNS zone on those nameservers also lists its own NS records. Normally the two lists match.
When a resolver needs any record for the domain, it follows that delegation to one of the nameservers and asks it directly. Because of this, the nameservers decide which DNS provider is in charge, whichever company hosts the website.
How to use the NS lookup tool
- Enter the domain, for example
example.com. A pasted web address is trimmed to the domain automatically. - Press Lookup NS.
- Read the table of nameservers with their IPv4 address and TTL.
- Compare the names with the nameservers your DNS provider asked you to set.
What the NS lookup results mean
Nameserver names
The names usually reveal the DNS provider. Names that end in a provider's own domain mean that provider answers for your zone, even if your website is hosted somewhere else.
IP address
Each nameserver is resolved to an IPv4 address. A dash means the nameserver's own name did not resolve, which can make the domain hard or impossible to reach and should be fixed with the provider.
TTL
The TTL is how long resolvers may cache the NS answer. NS records often have long TTLs, which is one reason a change of DNS provider can take hours to be seen everywhere.
Checking nameservers after a change
When you move DNS to a new provider, first copy every record into the new zone, then change the nameservers at your registrar. Keep the old zone active for a day or two so visitors with cached answers still reach the right place. Run this lookup during the switch to see which set of nameservers the internet currently returns.
Nameservers inside your own domain
Some domains use nameservers named under themselves, such as ns1.example.com for example.com. A resolver cannot look up that name without already knowing the answer, so the registry also stores the nameservers' IP addresses, called glue records. If you run your own nameservers like this, set the glue records at your registrar, and update them whenever the servers' IP addresses change.
Common uses
- Confirming a switch to a new DNS provider has taken effect.
- Finding out which company controls a domain's DNS before editing records.
- Checking that a domain has at least two nameservers for redundancy.
Common problems and fixes
No NS records found. The domain may not be registered, may have expired, or may have no nameservers set at the registrar. Check its status with the WHOIS Lookup.
Old nameservers still appear. NS answers are cached. Wait for the TTL to expire, and make sure the change was saved at the registrar rather than only inside the DNS provider's panel.
Only one nameserver. Add a second at your DNS provider so the domain stays reachable if one server fails.
Related tools
- DNS Lookup shows every common record in the zone.
- DNS Propagation Checker compares NS answers across public resolvers.
- WHOIS Lookup shows the nameservers held at the registry.
- Domain DNS Health Checker tests nameserver redundancy alongside other settings.
Frequently asked questions
What is the difference between nameservers and web hosting?
Nameservers answer DNS questions for a domain, while web hosting stores and serves the website files. They are often from different companies. The nameservers can belong to one provider while the A record inside that zone points to a website hosted somewhere else entirely.
How many nameservers should a domain have?
At least two, which many registries and registrars require. Two to four is typical. Ideally they sit on separate networks, so if one server or network has an outage the other can still answer and the domain stays reachable for visitors and email.
How long does a nameserver change take?
The registry usually publishes the new nameservers within minutes to a few hours, but resolvers may keep the old NS answer until its TTL runs out. In practice most visitors see the change within a day, and it can take up to 48 hours to reach everyone.
Why does the NS lookup show different nameservers than my registrar?
Either the change has not been saved at the registrar, or resolvers are still serving a cached answer. Confirm the nameservers listed in the WHOIS Lookup, which come from the registry. If those are correct, wait for caches to expire and check again later.
What does a dash in the IP address column mean?
It means the nameserver's own hostname did not resolve to an IPv4 address when we checked. Resolvers need that address to ask the nameserver anything. If it continues, contact your DNS provider, because a nameserver that cannot be found makes the domain harder or impossible to reach.
Can I change my nameservers myself?
Yes. Nameservers are changed in your account at the registrar where the domain is registered, usually under a DNS or nameserver setting. Before switching, recreate all existing records at the new DNS provider, otherwise the website and email can stop working.
Does the NS lookup work for subdomains?
A subdomain normally shares the main domain's zone and has no NS records of its own, so the lookup may return nothing. If a subdomain has been delegated to a different DNS provider, its own NS records will appear. For the main nameservers, look up the main domain.