With lots of ways to download Youtube videos using online service, here is another easy method to extract audio from any Youtube video and download them. Suppose you are in search for a audio song which you would love to save it on your pc, then make a search on youtube, find the video and extract only the audio part. This can be a useful way to build your audio collection. So, to rip audio from Youtube, head over to video2mp3 which is a free Video to Audio Mp3 converter for Youtube.
All you need is the Youtube video url, enter it and wait till the audio is ripped off from the Video. It will automatically compress the mp3 audio music, for example a video of 6 min (usually 20mb) was reduced to 2mb audio by video2mp3. They also have a addon for firefox browser that allows you to download audio from youtube easily, but it is compatible with Firefox 2.0 version only.