Developer Submission: Playlist Converter now accepts YouTube playlists and can export playlists - MSPoweruser
Download YouTube Playlist to MP3, MP4, AVI, etc on Mac/Windows
GitHub - nikolinaneric/Youtube-to-Spotify-playlist-converter: An app that will iterate through youtube playlist you like and make the same playlist on your Spotify account
Download MediaHuman YouTube to MP3 Converter Alternative
Top 12 Free YouTube Playlist Downloader for Mac and Windows