Composed in the key of F♯ minor, "Walking on Air" is a deep house song[REF] set in a 4/4 time signature at a moderately fast tempo of 128 beats per minute.
Written by Perry, Klas Åhlund, Max Martin, Adam Baptiste, and Caméla Leierth, "Walking on Air" discusses a love "so strong that even heaven is jealous" [REF].