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!
Getyt - Getyt.eu is the fastest YouTube to mp3 & mp4 conversion website.
4k YouTube to MP3 - Convert YouTube to MP3 on macOS, PC and Linux absolutely for free! Download the entire YouTube playlist and create your audio collection.
4K Video to MP3 - 4K Video to MP3 helps to get audio from any video you want just in one click.
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GetVideo.at - Allows to download videos from popular video streaming sites. No need for installation.