Open source web-based SKOS browser and publishing tool


  • search and browse vocabularies
  • alphabetical index
  • thematic index
  • structured concept display
  • visualized concept hierarchy
  • multilingual user interface

Use cases

Access to controlled vocabularies for indexing, information retrieval and vocabulary development.

Current users

Try the Skosmos demo


  • one or more SKOS vocabularies
  • PHP capable web server
  • SPARQL triple store (we recommend Apache Jena Fuseki with jena-text)
  • HTTP cache (e.g. Varnish) - optional but recommended

See Installation in the Skosmos wiki for details.


Skosmos has been implemented mainly in PHP and javascript. Open source libraries used by Skosmos include:

  • Composer, EasyRDF, Twig, jQuery, jsTree, Bootstrap, typeahead.js, URI.js, Punic

Skosmos source code is tested with PHPUnit. For ensuring a consistent experience with all devices we rely on BrowserStack.


Skosmos provides a REST-style API and Linked Data access to the underlying vocabulary data.

The API comes with a Swagger description. You can browse the Finto API documentation or build your own interactive documentation using the Skosmos swagger.json with Swagger tools.

The skosmos-users mailing list and web forum is available on Google Groups. This list is used for general discussion about Skosmos, asking for help, and announcements for new versions. All messages are public and anyone is welcome to join!

Skosmos is distributed as open source with the MIT license. The development is done openly on GitHub. You can participate by submitting bug reports, requesting new features, writing new translations or contributing code.

Skosmos is being developed at the National Library of Finland. Contact:

National Library of

Main publication

Please cite this if you are mentioning Skosmos in a research paper.

Suominen, O., Ylikotila, H., Pessala, S., Lappalainen, M., Frosterus, M., Tuominen, J., Baker, T., Caracciolo, C., Retterath, A. (2015). Publishing SKOS vocabularies with Skosmos. Manuscript submitted for review, June 2015.

Other publications

Suominen, O., Pessala, S., Tuominen, J., Lappalainen, M., Nykyri, S., Ylikotila, H., Frosterus, M., Hyvönen, E. (2014). Deploying National Ontology Services: From ONKI to Finto. In Proceedings of the ISWC 2014 Industry track.

Lappalainen, M., Frosterus, M., Nykyri, S. (2014). Reuse of library thesaurus data as ontologies for the public sector. In Proceedings of IFLA WLIC 2014, 16-22 August 2014, Lyon, France.

Suominen, O., Johansson, A., Ylikotila, H., Tuominen, J., Hyvönen, E. (2012). Vocabulary services based on SPARQL endpoints: ONKI Light on SPARQL. In Poster proceedings of the 18th International Conference on Knowledge Engineering and Knowledge Management (EKAW 2012).