Authoritative nameserver

Definition

An authoritative nameserver is a DNS server that publishes the source records for a DNS zone.

How it works

Every DNS zone has a set of servers holding the official copy of its records — the answers every resolver on the internet eventually traces back to. Your domain's delegation names those servers, and they respond with records like A, AAAA, MX, and TXT, each stamped with a time-to-live that tells resolvers how long the answer can be reused.

Example: If example.com delegates to ns1.example.net, that server is expected to answer for www.example.com.

Often confused: A recursive resolver hunts down and caches answers on behalf of clients; an authoritative nameserver is where the answers actually live.

Related terms

• Domain Name System (DNS)
• Nameserver
• Recursive resolver
• Zone file
• Time to live (TTL)

Learn more from Bitfoo

• Diagnose a site after a DNS change

Sources

• IETF RFC 1034: Domain Names — Concepts and Facilities
• ICANN Acronyms and Terms

Last reviewed 2026-07-19.