OBO-Edit is an open source ontology editor written in Java.
OBO-Edit features an easy to use editing interface, a simple but fast reasoner, and powerful search capabilities. It is optimized for reading and writing ontologies in the OBO biological ontology file format.
OBO-Edit is developed by the Berkeley Bioinformatics and Open Source Projects, and is funded by the Gene Ontology Consortium. Contributions to the OBO-Edit codebase are always welcome.