4K files are enormous. A breakdown of storage requirements:

You should only download 4K videos from directories where the content is:

In the digital ecosystem, an "index of 4K videos" refers not to a single website, but to a conceptual or practical catalog of ultra-high-definition content (3840 x 2160 pixels or higher). Unlike standard 1080p HD, 4K contains four times the pixel density, requiring specialized storage, bandwidth, and search methodologies.

This piece breaks down the three primary interpretations of a "4K video index": public domain archives, curated stock footage libraries, and metadata-based search engines.