What is an NS record?

An NS (Name Server) record is a DNS record that specifies which servers are authoritative for a domain. When a resolver needs to look up any record for your domain, it first finds the NS records to know which servers to ask. Every registered domain has NS records set at the registrar level.

How many nameservers should a domain have?

At least two, per RFC 1034. Two nameservers provide basic redundancy so your domain stays resolvable if one server goes offline. Most DNS providers assign two to four nameservers by default. Cloudflare assigns two, AWS Route 53 assigns four, and Google Cloud DNS assigns four.

What is lame delegation?

Lame delegation happens when an NS record points to a server that does not host the zone for that domain. The server responds with SERVFAIL or REFUSED instead of returning records. This usually occurs after a DNS provider migration when old NS records are left at the registrar.

How do I change my nameservers?

Log in to your domain registrar (the company where you bought the domain). Look for a "Nameservers" or "DNS" section in the domain settings. Replace the existing nameserver hostnames with the ones your new DNS provider gave you. Changes propagate to the TLD servers within a few hours, though full propagation can take up to 48 hours.

What's the difference between NS records at the registrar and in the zone?

The registrar-level NS records (called delegation records) live at the TLD and tell resolvers which servers to query for your domain. The zone-level NS records live inside your DNS zone file and should match the delegation records. If they disagree, most resolvers follow the delegation records, but the mismatch can cause inconsistent behavior.

What are glue records?

Glue records are A records for nameservers that exist under the domain they serve. If example.com uses ns1.example.com as its nameserver, a resolver cannot look up ns1.example.com without first knowing where to ask. Glue records break this circular dependency by providing the IP address alongside the NS delegation at the TLD.

Can NS records affect website speed?

Indirectly, yes. NS records themselves are only queried during the initial DNS resolution, which resolvers then cache. But if your nameservers are slow to respond or geographically distant from your visitors, that first lookup takes longer. After caching, subsequent requests skip the NS lookup entirely until the TTL expires.

Yes. No signup, no rate limit for normal use, no paywall. Queries go through our edge function to a public DoH resolver. We don't log the domains you check.

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