During World War II he secretly performed banned Polish music in Warsaw. The precarious circumstances affected Kędra's hands, but he overcame this. Settling back in Łódź after the German capitulation, he took part in the 1946 Concours de Geneve and the 4th Chopin Piano Competition, where he was awarded a 5th prize, which launched his concert career. In 1957 he settled in Vienna. He made many recordings, and died in Warsaw from cancer.