The best Document Manager alternative to Hydrus is TagStudio, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 10 alternatives to Hydrus and four of them are Document Managers so hopefully you can find a suitable replacement. Other interesting Document Manager alternatives to Hydrus are TagSpaces, Keepmark and Docspell.
TagStudio is a photo & file organization application with an underlying tag-based system that focuses on giving freedom and flexibility to the user. No proprietary programs or formats, no sea of sidecar files, and no complete upheaval of your filesystem structure.
Privacy-first, multi-device organizer for files and folders with customizable tags, color labels, note editing in markdown or HTML, Kanban boards, S3 object storage support, web page clipping, vendor lock-in free filename tagging, open source option, and multi-format preview.
Keepmark is a desktop, privacy first documents organizer. You can organize with it your files, email, bookmarks, tasks, news, and other resources. Its available for Windows, Linux and Mac.
Docspell is a personal document organizer. You'll need a scanner to convert your papers into files. Docspell can then assist in organizing the resulting mess 😉.
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