VLC
Different way of workingFreePlays whatever you have already downloaded, and can open a network stream directly.
Your files: Plays MP4, MKV, WebM and MP3 files without conversion.
Does 4K Video Downloader run on Linux?
Verdict: Yes
Yes. There is an official Linux build of 4K Video Downloader Plus, though the maker only lists it as supported on Ubuntu 22.04 and newer with the GNOME desktop.
The product page lists Windows 11, macOS 12 and newer, and Linux in the form of Ubuntu 22.04 64-bit with GNOME, or newer. That is a narrow statement of support. It usually runs on Mint and other Ubuntu-based systems as well, but those are not on the list, so if the app matters to you, stick close to plain Ubuntu.
Everything else works the way it does on Windows. You paste a link, choose a quality, and it saves the video or the audio. A paid licence is tied to your account rather than to Windows, so it carries across.
Files you already downloaded are ordinary MP4, MKV and MP3 files. They play in VLC or the built-in video player on Linux with nothing to convert.
Worth saying plainly: downloading from YouTube and similar sites is against their terms of use, and in Australia copying material you do not own is a copyright matter regardless of which system you use. The tool running on Linux does not change any of that.
4K Video Downloader on Linux, and alternatives
HandBrake
Different way of workingFreeFor converting a downloaded file into something a TV or an older phone will play.
Your files: Converts between the common video formats.
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