 " Breathe " is a country pop song with a length of four minutes and twenty @-@ one seconds . The song has soft rock and adult contemporary elements in it . It was written in common time and has a ballad tempo of 72 beats per minute . It is written in the key of D ♭ major , and Swift and Caillat 's vocals span one octave , from G ♭ 3 to B ♭ 4 . " Breathe " follows the chord progression D ♭ 5 – A ♭ – G ♭ . The song 's instrumentation relies mainly on acoustic guitar , which are often plucked , while , on occasion , violins provide the accompaniment . 
