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!
yt2mp3.org - Free online YouTube to MP3 Converter
YTmp3.net - Download your favorite YouTube videos as mp3 files without registration.
Point MP3 - Pointmp3 is one of the best and an easiest online tool that helps you to converts your favourite tracks on YouTube to the mp3 format that is of the highest quality.
OnlineVideoConverter.com - OnlineVideoConverter.
Ytmp3.cc - By using our converter you can easily convert YouTube videos to mp3 (audio) or mp4 (video) files and download them for free - this service works for computers, tablets and mobile devices.