Webulous provides a sidebar search across ontologies in the NCBO BioPortal. The ontologies in BioPortal can be used to create data-validations based on subclasses of a given term. Webulous also allows pre-defined templates with custom validations to be loaded from a dedicated Webulous server. Typically these templates are used for creating new ontology content. Populated templates can be submitted back to a Webulous server for processing using this Add-on. Webulous has been designed to support scientific curators and data annotators working at the European Bioinformatics Institute, but the functionality is sufficiently generic to be of use to other scientists working in the life sciences who build and use ontologies.