Ludwig Czaczkes was born and raised in Vienna. He studied music at the Academy of Music and the Performing Arts in 1912–1916, fought at World War I in 1916–1918 and continued his studies after the war. His teachers included Emil Sauer (piano), Ferdinand Löwe (conducting) and Josef Marx (composition). He also studied musicology at University of Vienna with Guido Adler and performed as pianist. From 1923 to 1931 he taught at the Academy of Music.
Czaczkes’ best-known theoretical work is his two-volume study Analyse des Wohltemperierten Klaviers: Form und Aufbau der Fuge bei Bach (1956) on The Well-Tempered Clavier.
Czaczkes died in Vienna in 1992, aged 93.