DNS Record Types Explained
A plain-English reference for DNS record types. Search for any record to see what it does, a realistic example value and practical notes, from everyday A and CNAME records to email and DNSSEC records.
How to use the DNS record explainer
- Search for a record type such as MX or a keyword like mail.
- Read the purpose and the example value.
- Check the notes for gotchas, such as where each record belongs.
Examples
What is an A record?
A
Maps a hostname to an IPv4 address, e.g. 93.184.216.34
What is an MX record?
MX
Mail server with a priority, e.g. 10 mail.example.com.
Frequently asked questions
What is the difference between an A and an AAAA record?
An A record points a hostname to an IPv4 address, while an AAAA record points it to an IPv6 address. Many hosts publish both.
When should I use a CNAME instead of an A record?
Use a CNAME to alias one hostname to another canonical name, for example www to the root domain. Do not use a CNAME at the zone apex, since it cannot coexist with other records there.
Why does an MX record have a number?
The number is a priority. When several mail servers are listed, senders try the lowest priority value first, which lets you set primary and backup mail servers.
What are SPF, DKIM and DMARC records?
They are email authentication policies published as TXT records. SPF lists allowed sending servers, DKIM publishes a signing key, and DMARC tells receivers how to handle failures.
What is a TXT record used for?
A TXT record stores free-form text. It is commonly used for domain ownership verification and for email policies like SPF, DKIM and DMARC.
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