Great Downloader easy to use can convert into multiple file formats. Fast and impressive
AVS Video Converter - AVS Video Converter is a handy software for converting to and from major video formats like 4K UHD, MP4, VOB, WMV, 2K QHD, DVD, MPEG4, DCI 4K, MOV, and more.
Video DownloadHelper - Browser extension to download videos from the Web
Transcoder - Transcoder is a free command-line-based video converter that allows you to convert any size of video into a range of audio and video formats.
youtube-dl-gui - A cross platform front-end GUI of the popular youtube-dl written in wxPython.
VSDC Free Video Editor - VSDC Free Video Editor is a video programming that permits you to alter video records and make recordings of different kinds.
Youtube Video and Audio Downloader - Download YouTube videos in all available formats and extract the original audio files.