What Is an A Record?
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Table of Contents
- What is an A record?
- How A records work
- Common uses for A records
- Managing A records in DNSimple
- Have more questions?
What is an A record?
An A record (record type 1) maps a domain name to an IPv4 address. The “A” stands for Address. When someone visits www.example.com, the A record tells their device which server IP (like 192.0.2.1) to connect to.
A records are one of the most common DNS record types. When you open a website, send email, or connect to an online service, DNS typically uses A records (or their IPv6 counterpart, AAAA records) to turn domain names into addresses.
How A records work
Here is what happens when you type a domain name like www.example.com into your browser:
- Your computer’s DNS resolver asks for the IP address associated with
www.example.com. - The query reaches the domain’s authoritative name servers, for example DNSimple’s name servers if the domain uses DNS hosting at DNSimple.
- The name server finds an A record for
www.example.compointing to an IPv4 address (for example,192.0.2.1). - The name server sends that IP address back to your resolver.
- Your browser connects to the server at that address.
This is why you can type a domain name instead of memorizing a string of numbers.
Common uses for A records
A records connect domain names to services on the internet:
Website and service hosting: Point a domain at the server running your website, mail server, or other online service.
Redundancy and load balancing: You can add multiple A records for the same domain, each pointing to a different server IP. That gives you two options:
- Load balancing: Resolvers and browsers spread requests across the addresses, so traffic is shared between servers.
- Basic redundancy: Many clients try another address if the first one does not respond. DNS keeps returning every address, though, including one whose server is down, so this is not health-checked failover.
Multiple domains, one address: Different domain names can point to the same IP address. Each domain gets its own A record, but they all resolve to that shared server. This is common when you host several sites on one machine.
The technical details are in RFC 1035, Section 3.4.1 if you want to dig into the specification.
Managing A records in DNSimple
You can manage A records in DNSimple’s record editor. Add new records, remove old ones, or update IP addresses as needed.
For detailed steps, check out our guide: Manage A Records.
Have more questions?
If you have additional questions or need any assistance with your A records, just contact support, and we’ll be happy to help.