TXT record
A TXT record is a DNS entry that holds arbitrary text, originally meant for human-readable notes (RFC 1035) but now used almost entirely to carry machine-readable policy strings that other systems parse automatically. SPF policies, DKIM public keys, DMARC policies, and one-off domain-ownership verification strings for services like a cloud provider or SSL certificate issuer are all published as TXT records on specific names, and a domain can publish multiple unrelated TXT records at once since each is just a line of text with no structure the DNS protocol itself enforces. Because TXT records have no type-specific syntax validation at the DNS layer, a malformed SPF or DKIM TXT record can be published without any error, only surfacing as a mail-authentication failure once a receiving server actually tries to parse it.
By AdminKit team, Netbase JSC · Updated