SiYuan vs Trilium Notes

SiYuan and Trilium Notes are both self-hosted, open-source personal knowledge base apps, but they organize information differently and price access…

Best for SiYuan: SiYuan fits users who want a graph-oriented, block-based note structure with built-in FSRS spaced-repetition flashcards and native mobile apps for iOS, Android, and HarmonyOS.
Best for Trilium Notes: Trilium Notes fits users who prefer a hierarchical, tree-based note organization, need to encrypt individual notes with AES-128-CBC, or are managing very large note collections (documented at 100,000+ notes) without ever paying.

At a Glance

 SiYuanTrilium Notes
Primary categoryProductivityProductivity
RatingNot documentedNot documented
Pricing modelFree and open source, with optional paid PRO features and cloud subscriptionopen-source
Starting priceFree (core app); PRO features from $64 one-timeFree
Free planYesNot documented
Free trialNot documentedNot documented
PlatformsWeb, iOS, Android, Mac, WindowsWeb
Team collaborationNot documentedNot documented
AI featuresNot documentedNot documented
Public APIYesYes

Key Differences

Pricing & Licensing

SiYuan: SiYuan's core is free (AGPL-3.0), but official cloud sync requires a one-time paid PRO ($64) or Subscription ($148) tier.

Trilium Notes: Trilium Notes is fully free and open source with no paid tier at all, for any feature.

Whether advanced features are ever gated behind payment changes total cost of ownership over time.

Note Structure Model

SiYuan: SiYuan uses block-level editing with bidirectional linking, backlinks, and a knowledge graph to connect notes non-hierarchically.

Trilium Notes: Trilium organizes notes in a tree structure, with the ability to clone a single note into multiple locations in the hierarchy.

A graph-based versus tree-based mental model changes how users navigate and structure large note collections.

Native Mobile Support

SiYuan: SiYuan has native apps for iOS, Android, and HarmonyOS, alongside Windows/macOS/Linux desktop and Docker/web deployment.

Trilium Notes: Trilium has no official mobile app; only an unofficial community Android client (TriliumDroid) and PWA browser support exist.

Official native mobile apps typically offer more reliable performance and support than unofficial community clients.

Spaced Repetition & Study Tools

SiYuan: SiYuan has built-in flashcard review using the FSRS spaced-repetition algorithm.

Trilium Notes: No flashcard or spaced-repetition feature is documented for Trilium Notes.

Built-in spaced repetition turns a notes app into a study tool without needing a separate flashcard app.

Note Encryption

SiYuan: Individual note encryption is not documented for SiYuan; privacy instead relies on self-hosting and local data control.

Trilium Notes: Trilium supports password-protecting individual notes using AES-128-CBC encryption.

Per-note encryption lets users protect specific sensitive content without encrypting an entire vault or relying solely on server access control.

Feature-by-Feature

Note Organization & Editing

FeatureSiYuanTrilium Notes
Hierarchical/tree notes with cloningNot documentedAvailable
Block-level editing (20+ block elements)AvailableNot documented
Multiple note types (canvas, Mermaid, mindmap, code)Not documentedAvailable
Note revisions/versioningNot documentedAvailable
Database/table/collection viewsAvailableAvailable

Knowledge Tools

FeatureSiYuanTrilium Notes
Bidirectional linking/backlinksAvailableNot documented
Knowledge graph viewAvailableNot documented
Spaced-repetition flashcardsAvailableUnavailable
PDF annotationAvailableNot documented
REST API and scriptingNot documentedAvailable

Platform & Access

FeatureSiYuanTrilium Notes
Native mobile appsAvailableUnavailable
Individual note encryptionNot documentedAvailable
Self-hosted/Docker deploymentAvailableNot documented
Paid tier for extra featuresAvailableUnavailable
Handles very large note collections (100k+)Not documentedAvailable

Pricing Compared

Starting price reflects the lowest paid tier, not the full cost for every team size or usage level.

SiYuan

Free — $0 Lifetime
PRO Features — $64 one-time (discounted from $96) One-time, lifetime access
Subscription — $148/year (discounted from $296) Annual subscription

Trilium Notes

Self-Hosted (Open Source) — Free N/A

Pros & Cons

SiYuan

Pros

  • Fully free and open source core application
  • Strong data ownership with local Markdown and JSON storage
  • Active open-source community with over 45,000 GitHub stars
  • Works fully offline with no forced cloud dependency
  • Flexible self-hosted sync options via WebDAV or S3

Cons

  • Community and some documentation lean toward Chinese-language users
  • Steeper learning curve than mainstream consumer note apps
  • Smaller plugin ecosystem than more established tools like Obsidian
  • Official cloud sync requires a paid PRO purchase or subscription
  • Company backing and long-term roadmap are less publicly documented than VC-backed competitors

Trilium Notes

Pros

  • Completely free and open source with no subscription cost
  • Strong privacy through local-first storage with no telemetry or vendor lock-in
  • Highly flexible unlimited-depth hierarchy with powerful note cloning
  • Actively developed again after the TriliumNext community revival
  • Well suited to large, deeply cross-referenced personal knowledge bases

Cons

  • Steeper learning curve than simple flat note apps due to the hierarchy and relations model
  • No official hosted cloud service, requiring self-hosting or local setup for cross-device sync
  • Interface feels more technical and less polished than consumer apps like Notion
  • Mobile experience has historically lagged behind the desktop and server experience
  • The project underwent a maintenance-mode scare in 2024 before the community fork took over

Use Cases

Choose SiYuan: SiYuan fits users who want a graph-oriented, block-based note structure with built-in FSRS spaced-repetition flashcards and native mobile apps for iOS, Android, and HarmonyOS.
Choose Trilium Notes: Trilium Notes fits users who prefer a hierarchical, tree-based note organization, need to encrypt individual notes with AES-128-CBC, or are managing very large note collections (documented at 100,000+ notes) without ever paying.
Need both: There's no clearly documented complementary scenario here - both are full personal knowledge base apps competing for the same core job, so most users would pick one as their primary note system rather than running both in parallel.

SiYuan

  • Personal knowledge base with linked notes — An individual builds a personal knowledge base using block references and bidirectional links to connect related ideas over time.
  • Privacy-conscious self-hosted note sync — A privacy-conscious user syncs notes across devices using self-hosted WebDAV or S3 storage instead of a proprietary cloud service.
  • Research organization with block-level references — A researcher organizes findings and references at the block level across many interconnected documents.

Trilium Notes

  • Personal knowledge base — Build a large, deeply organized second brain using unlimited-depth note hierarchies and cloning.
  • Self-hosted alternative to Evernote or OneNote — Move notes off third-party cloud services onto a self-hosted, privacy-respecting platform.
  • Developer documentation and snippets — Organize technical documentation and code snippets with syntax highlighting and structured tags.

Frequently Asked Questions

Is Trilium Notes completely free?

Yes, Trilium Notes is free and open source with no paid tier at all.

Does SiYuan cost money?

The core app is free (AGPL-3.0), but official cloud sync requires a one-time PRO tier ($64) or Subscription tier ($148).

Which app has spaced-repetition flashcards?

SiYuan, via built-in flashcard review using the FSRS algorithm. This isn't documented as a Trilium feature.

Does Trilium have an official mobile app?

No - Trilium has no official mobile app, only an unofficial community Android client (TriliumDroid) and PWA support for browser-based mobile access.

Can I encrypt individual notes?

Trilium supports password-protecting individual notes with AES-128-CBC encryption. Per-note encryption is not documented for SiYuan.

Which tool is documented to handle very large note collections?

Trilium Notes documents handling 100,000+ notes. A similar scale claim is not documented for SiYuan.

Read the full SiYuan review · Read the full Trilium Notes review