Freesound is a collaborative repository of Creative Commons licensed audio samples with more than 400,000 sounds (as of January 2019). Sounds are uploaded to the website by its users, and cover a wide range of subjects, from field recordings to music samples and synthesized sound effects. Audio content in the repository can be tagged and browsed by folksonomic means as well as standard text-based search. Audio content in the repository is also analysed using the open-source audio analysis tool Essentia, which powers the similarity search functionality of the site, and the Audio Commons Audio Extractor tool. Freesound has a RESTful API through which third-party applications can access and retrieve audio content and its metadata.
Freesound content is made available in the Audio Commons Ecosystem, including the automatically extracted semantic audio properties and timbral models.
Freesound was started in 2005, and is still developed and maintained at the Music Technology Group of Univeritat Pompeu Fabra, Barcelona, Spain. Freesound’s original goal was to give support to sound researchers, who often have trouble finding large royalty-free sound databases to test their algorithms, and to sound artists, who use pre-recorded sounds in their pieces. Nowadays Freesound has become one of the most popular sites for sharing sound samples, with ~55,000 unique visits per day and more than eight million registered users.