About the Metadata Standards Index
The Metadata Standards Index (MSI) is a comprehensive reference of metadata standards, vocabularies, schemas, application profiles, ontologies, and specifications used across the information sciences. It provides structured descriptions, typed links to official resources, and encyclopedic overviews for each standard.
The index currently covers 226 standards across 16 subject domains, with 1819 curated resource links to specifications, documentation, serializations, validators, and more.
Purpose
Metadata professionals, developers, students, and researchers often need to discover, compare, and reference metadata standards. Information about these standards is scattered across organizational websites, specifications portals, registries, and academic papers. The MSI brings this information together in a structured, searchable format.
For each standard, the index provides:
- Structured metadata including publisher, version, license, and status
- Typed links to specifications, namespaces, serializations, documentation, and tools
- An encyclopedic overview with background, purpose, key elements, and related standards
- Cross-references to related standards within the index
Maintained By
The Metadata Standards Index is a project of the DCMI Education Committee, specifically the Metadata Standards and Revisions Working Group.
The Dublin Core Metadata Initiative (DCMI) is an international organization supporting innovation in metadata design and best practices. DCMI's Education Committee develops resources and curricula for metadata education and professional development.
Methodology
Standards were gathered from established reference sources in the metadata community and supplemented with editorial knowledge of the broader landscape. The selection covers standards actively used in practice as well as historically significant ones that shaped the field.
For each standard, structured data was extracted from the official website, including titles, publishers, links, and version information. Where official pages were insufficient, editorial knowledge was used to fill gaps. Data provenance is tracked and noted in each record.
The index follows the principle of linking, not storing: specification files, PDFs, and serializations are referenced by URL rather than hosted locally. The authoritative source is always the standard's own maintainer.
Complementary Registries
Several registries catalog standards in specific domains. FAIRsharing maps standards, databases, and policies for FAIR research data, primarily in the life and biomedical sciences. BioPortal provides deep technical access to biomedical ontologies. Linked Open Vocabularies indexes RDF vocabularies on the Semantic Web.
The MSI takes a broader, cross-domain view — covering standards used across libraries, cultural heritage, archives, government, media, and the web. Its focus is educational: providing structured descriptions and encyclopedic overviews for metadata professionals and students, rather than technical ontology browsing or policy mapping.
Classification
Standards are classified by type and subject domain:
Types
A defined set of properties for describing resources (e.g. Dublin Core, MODS)
A selection and constraint of elements from one or more schemas for a specific use case
A controlled vocabulary or syntax rule for populating metadata values
A formal OWL/RDF knowledge representation (e.g. FOAF, Schema.org)
A structured set of terms broader than a simple encoding scheme
An abstract model not tied to a specific serialization (e.g. FRBR, CIDOC-CRM)
A format primarily for data interchange (e.g. MARC21, OAI-PMH)
A broader technical specification that includes metadata components (e.g. IIIF, EPUB)
Subject Domains
Open Data
The structured data behind the Metadata Standards Index is openly available on GitHub under a Creative Commons Attribution 4.0 International license. You are free to share and adapt the data for any purpose, provided you give appropriate credit. Corrections, additions, and suggestions are welcome.