Best Open Source Note Taking & Knowledge Management Tools in 2026

Apps for capturing notes, organizing information, and building personal knowledge systems and second brains.

5 open source note taking & knowledge management tools — ranked by GitHub stars. Browse all

A modern, open-source, self-hosted knowledge management and note-taking platform designed for privacy-conscious users and organizations.

Hierarchical personal knowledge base with powerful note-taking, rich text editing, and scripting capabilities.

Real-time collaborative markdown note editor you can self-host — write together with rich formatting and seamless sharing.

Markdown-based note-taking app with powerful live queries, templates, and a pluggable scripting system for power users.

A self-hosted personal knowledge base that turns markdown notes into an AI-augmented knowledge graph with semantic search and wiki synthesis.