ClipConverter.cc - ClipConverter.
MediaHuman YouTube to MP3 Converter - Extracts MP3 audio from YouTube, Vimeo, Dailymotion, Mixcloud, Bandcamp, SoundCloud and many others. Available for macOS, Windows and Ubuntu/Linux. FREE!
OnlineVideoConverter.com - OnlineVideoConverter.
YTmp3.net - Download your favorite YouTube videos as mp3 files without registration.
VidToMP3.com - VidToMP3.
Anything2MP3 - Anything2MP3 is a free online SoundCloud and YouTube to MP3 transformation device which permits you to change over and download SoundCloud and YouTube recordings to MP3.