Born in Fresno, California, Frank Thomas attended Stanford University, where he was a member of Theta Delta Chi fraternity and worked on campus humor magazine The Stanford Chaparral with Ollie Johnston. After graduating from Stanford, he attended Chouinard Art Institute, then joined The Walt Disney Company on September 24, 1934 as employee number 224. There he animated dozens of feature films and shorts, and also was a member of the Dixieland band Firehouse Five Plus Two, playing the piano.