TXT record

A TXT record (short for text record) is a type of resource record in the Domain Name System (DNS) used to provide the ability to associate some arbitrary and unformatted text with a host or other name, such as human readable information about a server, network, data center, and other accounting information.

A domain is not limited to having only one text record. Any fully qualified domain can potentially have several records. Each record can have one or more character strings.

Common uses include defining to verify domain ownership or in setting up Sender Policy Framework,DomainKeys, DomainKeys Identified Mail records which are used to validate legitimate email sources from a domain, and Zero-configuration networking DNS-based service discovery.

To store new types of information, the experimental RFC 1464 suggests a structured format in TXT data fields. The format consists of the attribute name followed by the value of the attribute. The name and value are separated by an equals sign (=).

The general syntax is:

Example:

The attribute name is considered case-insensitive.

During lookups, TXT records that do not contain an unquoted "=" are ignored. TXT records that seem to contain a null attribute name, that is, the TXT-DATA starts with the character "=", are also ignored.

Leading and trailing whitespace (spaces and tabs) in the attribute name are ignored unless they are quoted (with a "`").

Note that most DNS server implementations require a backslash (\) or double quote (") in a text string to be quoted with a preceding backslash. Accent grave ("`") was chosen as a quoting character in this syntax to avoid confusion with "\" (and remove the need for confusing strings that include sequences like "\\\\").

All printable ASCII characters are permitted in the attribute value. No characters need to be quoted with a "`". In other words, the first unquoted equals sign in the TXT record is the name/value delimiter. All subsequent characters are part of the value.

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