Matching of language tags

Type of document:
Best practice

IETF RFC 4647, "Matching of Language Tags," document describes a syntax, called a "language-range", for specifying items in a user's list of language preferences. It also describes mechanisms for comparing and matching these to language tags. This document, in combination with RFC 4646, replaces RFC 3066.

RFC 4646 and RFC 4647 were also published together under the number IETF BCP (Best Current Practice) 47.

Workflow stage:
1.3, 1.8, 1.10
Business value:

Applicable to a broad range of applications requiring language identification, particularly computer systems: terminology, lexicography, information management, documentation archival and retrieval, information services, information technology, search engines, and multilinguistic cultural and economic exchange.

Possible applications include programmed selection of a language among multiple valid values, or content selection.

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