metadb is a public database consisting only of free/libre data, aimed to help other projects and people in the free software community to access common information.

Who is using MetaDB

InternetRadio Simple Android app for searching and listening to Internet radio stations.
License App for Android to search software licenses and read their full text version, as defined by SPDX.

How to use the database

The simplest way to get started is the public API.

At the moment metadb is read-only, meaning that it is not possible to edit data from this website. Instead, we import datasets from various sources and try to integrate them such that they can be reused easily and more effectively by any free project. We encourage anybody who wish to improve the data, to contribute directly to the communities maintaining the relative datasets.

We also offer a public SPARQL endpoint at It accepts both GET and POST request with the parameter query=...

Available datasets

Dataset License Graph IRI Description
Apache Projects Directory Apache License, Version 2.0 <graph:apache-projects> Catalog of Apache Software Foundation projects.
FOAF <graph:foaf> An archive of FOAF files. FOAF describes persons, their activities and their relations to other people and objects.
Free Software Directory GNU Free Documentation License <graph:free-software-directory> A project of the Free Software Foundation to catalog free software that runs under free operating systems - particularly GNU and Linux.
GRID CC0 1.0 <graph:grid> GRID is comprised of a worldwide collection of institutes associated with academic research. The institutes contained are distinguished by a unique identifier, GRID ID. Each unique GRID record also contains relevant metadata, as well as relationships between associated institutes.
h-node CC0 1.0 <graph:h-node> The h-node project aims at the construction of a hardware database in order to identify what devices work with a fully free operating system.
lexvo CC-BY-SA 3.0 <graph:lexvo> Lexvo brings information about languages, words, characters, and other human language-related entities to the Linked Data Web and Semantic Web.
Open Food Facts ODbL, DbCL <graph:openfoodfacts> Open Food Facts is a food products database made by everyone, for everyone.
peers meta CC0 1.0 <graph:peers-meta> META is a small collection of metadata about free software. Public Domain <> A dataset of RDF URI prefixes.
Princeton WordNet WordNet 3.0 license <graph:princeton-wordnet> WordNet is a large lexical database of English. Nouns, verbs, adjectives and adverbs are grouped into sets of cognitive synonyms (synsets), each expressing a distinct concept. Synsets are interlinked by means of conceptual-semantic and lexical relations.
Project Gutenberg GNU Free Documentation License 1.2 <graph:gutenberg>

The Project Gutenberg Catalog.

Project Gutenberg offers over 53,000 free ebooks: choose among free epub books, free kindle books, download them or read them online.

Radio Browser Public Domain <graph:radio-browser> A community database to collect as many internet radio stations as possible.
SPDX <graph:spdx>

The Software Package Data Exchange specification is a standard format used to document information on the software licenses under which a given piece of computer software is distributed.

The SPDX standard helps facilitate compliance with free and open source software licenses by standardizing the way license information is shared across the software supply chain. SPDX reduces redundant work by providing a common format for companies and communities to share important data about software licenses and copyrights, thereby streamlining and improving compliance.

Suggest new datasets

Currently, all datasets on metadb are added manually. If you would like to suggest a new dataset, please contact us.


This project is developed as an activity of the Peers Community.

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