Protégé Short Course June 23–25, 2026 @ Stanford University
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Free & Open Source
Protégé is a free, open-source OWL ontology editor
Used by researchers, organisations, and governments worldwide to build and manage ontologies. Available as Protégé Desktop for local use and WebProtégé for collaborative, browser-based editing.
Notable projects
OBO Foundry
Many ontologies in the Open Biological and Biomedical Ontology (OBO) Foundry are developed and maintained with Protégé.
WHO ICD-11
The World Health Organization used a WebProtégé-based environment to develop the International Classification of Diseases (ICD-11).
NCI Thesaurus
The National Cancer Institute Thesaurus, a widely used biomedical ontology, was developed and maintained using Protégé.
About Protégé
Designed for OWL 2 ontology development
Protégé supports the full ontology development lifecycle — from initial modelling through to reasoning, querying, and collaboration.
Community Supported
An active community of users and developers answers questions, maintains documentation, and contributes plug-ins.
OWL 2
Full support for the OWL 2 Web Ontology Language from the W3C.
Open & Extensible
Written in Java with a plug-in architecture, so it can be extended and adapted for different workflows and research needs.
