What an A record is
An A record, short for Address record, is the DNS entry that links a domain name to a single IPv4 address. When someone visits example.com, a resolver looks up the A record to discover the numeric address of the server hosting the site, then connects there.
How it works
An A record has three key parts:
- The name, such as
example.comorwww.example.com. - The value, which is an IPv4 address like
203.0.113.10. - The TTL, which sets how long resolvers may cache the answer.
A single name can have several A records pointing to different addresses, which spreads traffic across multiple servers for redundancy and basic load balancing. For IPv6 addresses, the equivalent record type is AAAA.
Why it matters
The A record is one of the most fundamental DNS records because it is what actually directs web visitors to a server. Moving a site to new hosting usually means updating its A record to the new server's IP. For example, if you migrate from a host at 203.0.113.10 to one at 198.51.100.20, you change the A record and, once caches expire, traffic follows. You can confirm a domain's A record with the WhatIP dns-lookup tool.