What is Chance Music?

Chance music, also called aleatoric music, is a type of composition in which random processes or unpredictable decisions are used to determine some elements of the music. These elements may include pitch, rhythm, dynamics, structure, or the order of musical events.

In chance music, the composer may use methods such as dice rolls, random number tables, computer algorithms, or performer choice to generate musical material. This approach reduces the composer’s direct control over certain aspects of the piece, allowing unpredictable results to shape the music.

Chance music became especially associated with 20th-century experimental composers, particularly John Cage, who used chance operations to create works where randomness played a central role in the composition process. The technique explores new forms of musical structure and challenges traditional ideas about authorship and control in music.