Open-source alternatives to Microsoft OneNote

AppFlowy is an AGPL-3.0 workspace with documents, databases, wikis, project management, offline support, desktop and mobile apps, AI features, and self-hosted sync.

Pricing: Free and open source; hosted sync and commercial services may be available.

• Offline support and self-hosting
• Documents, databases, and AI
• Desktop and mobile apps
• Not based around plain Markdown vaults
• More workspace-oriented than PKM-focused

Memos is an MIT-licensed self-hosted notes application organized around a chronological timeline for thoughts, links, logs, and short notes.

Pricing: Free and open source under MIT; self-hosted deployment is available.

• Lightweight and easy to self-host
• Markdown support
• Fast note capture
• No Obsidian-style graph
• Limited knowledge-management features

Joplin is an AGPL-3.0-or-later cross-platform note-taking and PKM application with Markdown, end-to-end encryption, web clipping, attachments, plugins, offline use, and multiple synchronization options.

Pricing: Free and open source; optional hosted synchronization is available.

• Markdown and offline use
• End-to-end encryption
• Plugins, web clipper, and multiple sync options
• Less graph-focused than Obsidian
• More traditional interface
• Linking is less central

SiYuan is an AGPL-3.0 local-first PKM application with block references, documents, backlinks, graph views, databases, flashcards, rich editing, and Docker deployment.

Pricing: Free and open source under AGPL-3.0; some cloud functionality may be commercial.

• Local-first block references
• Graph view, databases, and spaced repetition
• Offline and Docker support
• Not a simple Markdown-vault model
• More complex data model
• Some cloud functionality is commercial

Tolaria is an AGPL-3.0 personal knowledge base built around plain Markdown files, YAML metadata, Git version control, Wikilinks, whiteboards, and local or cloud AI models.

Pricing: Free and open source under AGPL-3.0; verify current project hosting and deployment options.

• Plain Markdown and Git workflow
• Wikilinks and whiteboards
• Local/cloud AI with no mandatory account
• Younger project
• Smaller plugin ecosystem
• Less mature than Obsidian or Joplin

Notesnook is a GPL-3.0 privacy-focused note-taking application with end-to-end encryption, cross-platform clients, note linking, a web clipper, rich editing, offline support, and self-hostable synchronization.

Pricing: Open source under GPL-3.0 with self-hostable sync; hosted services may be available.

• End-to-end encryption and zero-knowledge design
• Desktop, web, mobile, offline, and web clipper
• Self-hostable sync
• Less focused on knowledge graphs
• No Obsidian-style plugin ecosystem
• Not plain-file oriented

Standard Notes is an AGPL-3.0 encrypted note-taking application focused on privacy, longevity, secure synchronization, offline access, and a self-hosted server option.

Pricing: Open-source main app with self-hosting; some advanced hosted features require a subscription.

• End-to-end encryption and offline access
• Cross-platform and self-hostable
• Strong privacy and long-term data portability
• Less focused on backlinks and graphs
• Some hosted features are paid
• Less flexible than Obsidian for plugins

Beaver Notes is an MIT-licensed offline-first note-taking application with local storage, Markdown, note linking, attachments, drawings, LaTeX, and user-controlled synchronization.

Pricing: Free and open source under MIT with local-first use and optional user-controlled synchronization.

• Offline-first local storage
• No mandatory account or telemetry
• Markdown, links, attachments, drawings, and LaTeX
• Smaller ecosystem
• Limited advanced PKM functionality
• No large plugin marketplace

Darkwrite is an AGPL-3.0 offline-first note editor focused on local writing, formatting, lists, images, customization, and export across desktop platforms.

Pricing: Free and open source under AGPL-3.0 with a local-first workflow.

• Offline-first and local data
• Cross-platform and customizable
• Simple open-source editing
• Much simpler than Obsidian
• Limited backlinks and graph functionality
• Small ecosystem

Justnote is a GPL-2.0 private note-taking application with synchronization and end-to-end encrypted data, focused on simple cross-device notes rather than complex personal knowledge management.

Pricing: Free and open source under GPL-2.0; verify current project availability.

• Privacy-focused encrypted synchronization
• Cross-device access
• Simple open-source interface
• Small project
• Limited PKM functionality
• No Obsidian-style graph or plugin ecosystem