g:Orth makes use of orthologous gene mapping information from the Ensembl database. It enables the user to retrieve orthologous genes corresponding to their input gene list automatically. The mapping is executed in two-step manner by first converting the input gene IDs provided by the user to Ensembl ENSG identifiers, and then retrieving the corresponding orthologous gene information for target species. g:Orth can be used to transfer the knowledge collected for well studied model organisms to less studied species. Conducting enrichment analysis after orthologous mapping might lead to more comprehensible results than it would be possible when using only the original species.