Broadly speaking, the Domain Name System (DNS) associates domain names (such as example.com) with their IP addresses (such as 93.184.216.34). Within DNS, there are several types of records, such as A, CNAME, MX, PTR, and TXT.
But what is a TXT record, and what is it used for? Fundamentally, all that a TXT record does is associate arbitrary text with a domain or host name. The text can be intended for humans to read, or for remote systems to process. Here are some examples of common uses for TXT records:
- Email: The SPF, DKIM, and DMARC protocols all rely on TXT records to provide email configuration information.
For information about DKIM and SPF, please see this article.
- Domain ownership verification: TXT records are often used to prove ownership of a domain, as it is assumed that only the domain's owner can create, modify, and delete its TXT records.
For an example of proving domain ownership with a TXT record, please see this article.
- Notices and notifications: Because TXT records can contain any text, they sometimes provide general information or notifications about the domain (for example, “This domain name is reserved for testing”).
To view the TXT records for a domain, you can use an online tool such as https://mxtoolbox.com/TXTLookup.aspx. Alternatively, you can use a command line program like dig. For example:
user@host:~$ dig TXT example.com ;; QUESTION SECTION: ;example.com. IN TXT ;; ANSWER SECTION: example.com. 3198 IN TXT "v=spf1 -all" example.com. 3198 IN TXT "wgyf8z8cgvm2qmxpnbnldrcltvk4xqfn"
