Notion is published by Notion Labs. This page compares only projects with an explicit relationship to it; shared categories alone never create an alternative claim.
Recommended order uses OpenAlternative organic alternatives v4 (version 4). Relationship confidence, category fit, logarithmic popularity, as-of maintenance and freshness, bounded anomaly quarantine, and known-data penalties. Payment is fixed at zero.
A hard constraint removes a Project only when its stored fact is known and conflicts. Unknown facts remain visible, are called out below, and never become a negative claim.
Collaborative wiki with real-time editing and diagrams
Docmost is a documentation workspace with real-time collaborative editing, nested spaces, and diagram support built in rather than embedded from elsewhere.
Team knowledge base that stays fast as it grows
Outline is a documentation workspace built around search and structure rather than infinite nesting. Collections, a strong editor, and genuinely fast full text search make it usable at the size where most wikis become write-only.
Project boards that work offline and stay local
Focalboard is a board and table tool that runs as a desktop application against local files, or as a server for a team. It covers the kanban, table, and calendar views most planning needs without a subscription or an account.
Documents, whiteboard, and database in one canvas
AFFiNE puts a document editor and an infinite canvas over the same content. A page can be read as a document or arranged spatially as a whiteboard, and edits in one mode are edits in the other.
File sync, sharing, and a suite of apps on your own server
Nextcloud started as file sync and grew into a full collaboration suite: documents, calendar, contacts, chat, and an application ecosystem on top of the same account system.
Groups appear only when at least two credible projects qualify.
Docmost, Outline, Focalboard