Musically, "Hung Up" is a dance-pop, disco and nu-disco song. According to "The New York Times", the song has vaguely familiar hooks, sustained overlays of the string arrangement and acoustic guitar enfolding the music to create a haze like sound. "Billboard" described the music as frothy, nonsensical and joyous. The instant familiarity of the sampled music is changed by Stuart Price and Madonna by adding a chugging groove and a chorus which singles it out as an independent song. Alongside the ABBA sample, "Rolling Stone" said that the song also incorporates elements of Madonna's older songs like "Like a Prayer" and "Holiday" and features fleeting quotes from bands like S.O.S. and the Tom Tom Club.