Convert audio file to text

if you have a song and you want the lyrics....search for the song name on google.

if you have an audio recording of voice only...use a dictation software such as dragon, google voice, or other such dictation software. none are 100% perfect and only a few are free.

It's actually a speech and it's some kinda hard to transcribe it and I'm lacking out of time. do you know a link which I can download a dictation software for free? Please help me with this. Thanks for the time