Extract Audio from YouTube Videos

I wanted to get an mp3 of a video on YouTube. There are sites that will do it for you, but I wanted a little more control.

Turns out it was pretty easy with free software.

1) Download the flv video

I used the open-source YouTube Downloader from Sourceforge. With that Java application I just needed to drag the URL from my browser onto the application and it would start downloading. I could even download multiple videos at once.

2) Extract the audio

ffmpeg was all I needed in this case. The command I used was:

ffmpeg -i youtubevideo.flv output.mp3

Simple as that!