32 Variations in C minor

32 Variations on an Original Theme in C minor, WoO 80 (German: 32 Variationen über ein eigenes Thema), is a composition for solo piano by Ludwig van Beethoven, written in 1806.

The work consists of an eight-bar main theme and 32 variations. A chord progression in the left hand, based upon a descending chromatic bass, serves as an important structural device. The short and sparse melodic theme, as well as the emphasis on the bass line, reflect a possible influence of the chaconne and the Folia. The variations differ in character, technical difficulty and dynamics.

Typically, performances of this piece last from 10 to 12 minutes.

The piece proved popular, receiving a favorable review in the Allgemeine musikalische Zeitung (Leipzig) in 1807, and remains popular today. Nevertheless, Beethoven did not see fit to assign it an opus number. It is said that later in his life he heard a friend practicing it. After listening for some time he said "Whose is that?" "Yours", was the answer. "Mine? That piece of folly mine?" was his retort; "Oh, Beethoven, what an ass you were in those days!"