ABSTRACT jMIR is a free and open-source software suite designed for applications related to automatic music classification. jMIR includes the jAudio, jSymbolic and jWebMiner feature extractors, the ACE meta-learning framework, the ACE XML information exchange file formats, the jMusicMetaManager musical dataset management software and the Codaich, Bodhidharma MIDI and SAC musical datasets. The primary goals underlying jMIR are the provision of powerful ready-to-use software tools to music researchers with diverse ranges of technical backgrounds, the encouragement of research combining features derived from audio, symbolic and cultural sources of data, and the provision of a framework for iteratively and collaboratively developing further music information retrieval (MIR) tools and performing original music classification research.