SiYuan
FreemiumPrivacy-first local knowledge management with block-level references
About SiYuan
SiYuan is a privacy-first personal knowledge management system with 43000 plus GitHub stars built around block-level content referencing and bidirectional linking. Every paragraph heading list item and code block is an addressable block that can be referenced embedded and queried from anywhere in your knowledge base. This creates a knowledge graph at a granularity level below what Obsidian or Notion offer. The outline view hierarchical tags and database-style attribute views organize content flexibly. Built-in spaced repetition turns notes into flashcards for active learning. End-to-end encrypted cloud sync is available as a paid feature while local storage is completely free. Math equations Mermaid diagrams PlantUML charts and code blocks with syntax highlighting handle technical content. The editor supports both Markdown and WYSIWYG modes. Built with Go and TypeScript it runs as a desktop app on Windows macOS and Linux with mobile apps for iOS and Android. For power users who think in interconnected blocks rather than documents SiYuan provides deeper structural linking than any competitor.
Key Features
Pricing Plans
Free
- Local use
- All core features
- Desktop and mobile apps
- No cloud sync
Cloud
- All free features
- E2E encrypted sync
- Cloud storage
- Priority support
Pros
- Block-level referencing more granular than any competitor
- Spaced repetition built in for active learning
- End-to-end encrypted sync option for cross-device use
- Rich content support including math diagrams and code
- Desktop and mobile apps for all platforms
- Completely free for local use
Cons
- Steeper learning curve than simpler note apps
- Block reference syntax takes time to master
- Cloud sync requires paid subscription
- Smaller community than Obsidian or Notion
- Interface can feel overwhelming for simple notes
- English documentation sometimes lags Chinese original
Best For
- Knowledge workers who think in interconnected blocks and need granular references
- Students using spaced repetition for study alongside notes
- Privacy-focused users wanting encrypted sync across devices
Not Ideal For
- Users wanting simple straightforward note-taking
- Teams needing real-time collaboration
Potential Deal Breakers
- Cloud sync requires paid subscription
- Steep learning curve for block references
- Smaller English-speaking community
Data & Privacy
Local-first knowledge management. All notes stored on your device. End-to-end encrypted sync available. No unencrypted data leaves your control.
Who Is This For?
Hands-on tested 2026-05
Signup Experience
Download desktop app — no account needed for local use. Cloud sync subscription unlocks cross-device access. First notebook setup is guided and intuitive.
For Home Users
Strong Obsidian alternative with built-in sync at a reasonable yearly cost. Spaced repetition flashcards and graph view add value for learners. English community is growing but docs lag behind.
For Business Users
Better suited for individual knowledge workers than teams. End-to-end encrypted sync is a strong privacy feature. Limited collaboration tools make it a poor fit for team wikis.
Our Verdict
SiYuan goes deeper than Obsidian on structural knowledge linking. Block-level references and built-in spaced repetition are genuine differentiators. The learning curve is real but the payoff for power users is significant.