Hello
As it was said for other answers, as soon as you can hear on your computer something, AUDACITY becomes quickly a very good tool.
After, with the Mp3, it is possible to make it analyze FREE by the sites which accept that one deposits a Mp3... It is the case of SONGLE.JP which recommends the site SOUNDCLOUD... But it is never simple... The majority of the sites of analysis of the audio, know only the Youtube links. Making a mini video with the Mp3 and putting it on Youtube is a solution, otherwise, there are local tools on the computer that do the same thing very well. CHORDTRACER from IPE, which is not free, or Sonic Visualizer and its Add-On CHORDINO, which is free, allow a very good analysis of the Mp3 and help to make a musical statement.