DNS TXT record 255 characters limit
Domain name owners must be aware of the DNS TXT record 255 characters limit. This knowledge facilitates error-free modifications to DNS records, such as SPF, DKIM to name a few. TXT records store email authentication settings and domain-related information, with a maximum length of 255 characters as per DNS protocol.
Overcoming TXT record 255 characters limit
When the content of a TXT record exceeds 255 characters, it is necessary to divide it into smaller sections. To accomplish this, spaces are inserted every 255 characters, creating different segments within the record. TXT records with spacing are treated as a single unit by DNS resolvers and other systems. They ignore the spaces and consider the entire TXT record as a cohesive entity, enabling accurate reconstruction of the original text.
To illustrate this concept, imagine a lengthy sentence that surpasses the character limit. You would break it into shorter sentences or parts, fitting within the allowed length. Similarly, each segment in a TXT record is 255 characters long, and the spaces denote where the segments join to form the complete text. To understand the 255 characters limit of TXT records, consult industry-standard documentation such as RFC 7208 published by the Internet Engineering Task Force (IETF). It provides comprehensive guidelines for DNS-based email authentication protocols.
When a TXT record reaches the 255 characters limit, adding spaces enables storing and retrieving longer text strings. These spaces act as markers for segment boundaries, ensuring accurate reassembly of the original content during record processing.
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