Cerf was the first non-Japanese player to win the World Championship for Othello, in 1980.
His father, Bennett Cerf, was the co-founder of Random House books and panelist of What's My Line?. Jonathan appeared with Peter Gabel, as guests on the show on 12 March 1967. His mother, Phyllis Cerf, was co-founder of Random House's Beginner Books with Dr. Seuss. His brother, Christopher Cerf, wrote music for Sesame Street, voiced characters like Chrissy of Chrissy and the Alphabeats, and co-created Between the Lions. Cerf is second cousin of Ginger Rogers, Fred Astaire's dancing partner.