WARNING: This document is OBSOLETE.

Reserved prefixes are defined in the EPUB 3 Packages Specification.

EPUB Publications Reserved Prefixes

5 October 2016

Status of this Document

This document is subject to change at any time. The prefixes defined herein will never be removed, but may be deprecated.

Any use of the prefixes marked [draft] should be considered experimental.

Deprecated prefixes are identified by the label [deprecated]. These prefixes are no longer recommended for use.

Prefixes without a label are considered stable.

Requests for additions, modifications and clarifications can be made through the Issue Tracker. Pull requests are also welcome.

Refer to the IDPF Issue Reporting Guidelines for more information about the change request process.


This document defines the set of prefixes that Reading Systems are expected to recognize when used in EPUBĀ® Package Document metadata.

For more information about prefixes, including how to declare and use them in the Package Document, please refer to Vocabulary Association Mechanisms in the Publications specification.


This following prefixes are defined for use in package metadata.

Prefix IRI
a11y http://www.idpf.org/epub/vocab/package/a11y/#
dcterms http://purl.org/dc/terms/
epubsc http://idpf.org/epub/vocab/sc/#
marc http://id.loc.gov/vocabulary/
media http://www.idpf.org/epub/vocab/overlays/#
onix http://www.editeur.org/ONIX/book/codelists/current.html#
rendition http://www.idpf.org/vocab/rendition/#
schema http://schema.org/
xsd http://www.w3.org/2001/XMLSchema#