He was born in Hoosick Falls, New York. His father, John A. Eberle, was a local policeman, sign-painter, and publican (tavern-keeper). His elder brother was Big Band singer, Bob Eberly, who sang with the Jimmy Dorsey Orchestra. Ray started singing in his teens, with no formal training. In 1938, Glenn Miller, who was looking for a male vocalist for his big band, asked Eberly if he had any siblings at home who could sing. Bob said "yes", and Ray was hired on the spot. Music critics and Miller's musicians were reportedly unhappy with Eberle's vocal style but Miller stuck with him. Ray Eberle went on to find success with Miller, deeming the songs for Orchestra Wives, such as the jazz standard "At Last", to be among his favorites as there were songs he could "sink my teeth into, and make a story out of". He appeared in the Twentieth Century Fox movies, Sun Valley Serenade (1941) and Orchestra Wives (1942). He made one Universal film, Mister Big, making a cameo appearance as himself. Eberle mostly sang ballads. From 1940-43 he did well on Billboard (magazine)'s "College Poll" for male vocalist. Ray Eberle sang lead on "Sometime", composed by Glenn Miller in 1939, "Polka Dots and Moonbeams", "At Last", a number 9 chart hit on Billboard in 1942, and "To You", but Miller ran a tight ship and often fired people after one negative incident. Eberle was stuck in traffic one day during a Chicago engagement, and was late for a rehearsal. Miller fired him on the spot, and replaced him in June 1942 with Skip Nelson. After his departure from Miller, Eberle briefly joined Gene Krupa's band before launching a solo career. He later joined former Miller bandmate Tex Beneke's orchestra in 1970 for a national tour, and reformed his own orchestra later in the decade.