If you have a WAV file, you can easily convert it to MP3 using iTunes on Windows or Mac. Open it up in iTunes, then right-click on the file (control-click on Mac). Choose Convert Selection to MP3 in the Advanced Menu. If Convert Selection to MP3 is not listed, you probably need to go to iTunes Preferences and change your Import Settings to MP3 Encoder.
If you're not sure where iTunes has saved the new MP3, click File > Get Info, then look at the Where section at the bottom of the Summary tab.⬅ FAQ