Ludwig van Beethoven's Piano Sonata No. 29 in B♭ major, Op. 106 (known as the Große Sonate für das Hammerklavier, or more simply as the Hammerklavier) is a piano sonata widely viewed as one of the most important works of the composer's third period and among the greatest piano sonatas. Completed in 1818, it is often considered to be Beethoven's most technically challenging piano composition and one of the most demanding solo works in the classical piano repertoire.

Date of composition 1818
First published 1819 Artaria
Type Sonata
Tonality B-flat Major
Catalogue Op. 106
Approx. duration 40 minutes
Instruments Piano
Autotranslations beta Ludwig van Beethoven: Sonate pour piano n°29 en si bémol majeur, Op. 106 "Hammerklavier"
Ludwig van Beethoven: Sonata per pianoforte n. 29 in si bemolle maggiore, Op. 106 "Hammerklavier"
Ludwig van Beethoven: Sonate Nr. 29 für Klavier B-dur, Op. 106 "Hammerklavier"