According to the official documents, the music score was composed by Chaplin himself, and arranged with the assistance of Alfred Newman, who had collaborated with Chaplin on the music score of his previous film City Lights. Newman and Chaplin had a falling out near the end of the Modern Times soundtrack recording sessions, leading to Newman's angry departure.
The romance theme was later given lyrics, and became the pop standard "Smile", first recorded by Nat King Cole. A cover of this song by Jimmy Durante was also used in the trailer for the 2019 film Joker, in which the lead character also watches scenes from a showing of Modern Times after sneaking into a movie theatre.
Modern Times was the first film where Chaplin's voice is heard as he performs Léo Daniderff's comical song "Je cherche après Titine". Chaplin's version is also known as "The Nonsense Song", as his character sings it in gibberish. The lyrics are nonsensical but appear to contain words from French and Italian; the use of deliberately half-intelligible wording for comic effect points the way towards Adenoid Hynkel's speeches in The Great Dictator.
According to film composer David Raksin, Chaplin wrote the music as a young man wanting to make a name for himself. He would sit, often in the washroom, humming tunes and telling Raksin to "take this down". Raksin's job was to turn the humming into a score and create timings and synchronization that fit the situations. Chaplin was a violinist and had some musical knowledge, but he was not an orchestrator and was unfamiliar with synchronization. Along with Edward B. Powell, Raksin did receive screen credit for the music arrangements.[9] Raksin later created scores for films including Laura and The Day After.
