In case you want to convert a youtube video to a MP3 file, you could use one of the many online solutions. But if you don’t want all the advertising mess and are not afraid of using your terminal with bash, you can use the following solution.

If you have not already installed HOMEBREW do it now! (Homebrew makes it easy to use commandline tools Apple doesn’t include by default)

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

after this you can install FFMPEG and YOUTUBE-DL with the following command;

brew install ffmpeg youtube-dl

If everything went successful you can use the following line to convert youtube movies into MP3-files

youtube-dl --extract-audio --audio-format mp3 --prefer-ffmpeg https://www.youtube.com/watch?v=VIDEO_ID_HERE

If you want to download a playlist use the URL from youtube without the “v=VIDEO_ID” part

youtube-dl --extract-audio --audio-format mp3 -o "%(title)s.%(ext)s" YOUTUBE_URL_HERE