SiYuan is a free, open-source, privacy-first personal knowledge management app with block references and bidirectional links. See 2026 features and pricing.
SiYuan is an open-source personal knowledge management application developed by the B3log team, a group that has been building open source software since 2009 and working full-time on open source projects since 2018. The app is released under the AGPL-3.0 license with its full source code public on GitHub.
The core philosophy behind SiYuan is privacy and data ownership: notes are stored locally as Markdown files paired with JSON metadata, meaning users can read and move their data without relying on a proprietary format or a mandatory cloud account.
SiYuan has attracted a large and active open-source community, with its GitHub repository surpassing 45,000 stars, and it ships as native desktop apps for Windows, macOS, and Linux plus mobile apps for Android and iOS.
At the core of SiYuan is block-level referencing: every piece of content, whether a paragraph, heading, or list item, is a discrete block with a unique ID that can be linked or embedded anywhere else in a user's notes, enabling true bidirectional linking rather than simple page-to-page links.
A graph view visualizes the connections between blocks and documents, helping users see how their notes relate to one another as a network rather than a flat folder structure, a workflow similar to Obsidian's graph view.
Because sync is not tied to a mandatory proprietary server, users can sync their notes using third-party services like WebDAV, S3-compatible storage, or Resilio Sync, or opt into SiYuan's own official cloud sync service for convenience.
The core SiYuan application is free for both personal and commercial use, on a lifetime basis, and includes the full block-editing, Markdown, and offline feature set with no artificial limits on note count or local usage.
A one-time PRO purchase, priced around $64 (discounted from $96), unlocks integration with third-party sync and backup services such as Amazon S3 and WebDAV, useful for users who want automated sync without relying on SiYuan's own cloud.
A recurring Subscription plan, priced around $148 per year (discounted from $296), adds SiYuan's official cloud sync service, 8GB of official cloud storage, cloud asset hosting, and a cloud inbox for users who prefer a fully managed sync experience.
Yes, the core application with block editing, Markdown support, and offline access is free for both personal and commercial use.
Yes, SiYuan is fully open source and released under the AGPL-3.0 license with its code public on GitHub.
Yes, SiYuan is offline-first and stores all notes locally by default.
A block reference lets any paragraph, heading, or list item be linked to or embedded in another location in a user's notes, enabling bidirectional linking.
Yes, users can sync notes using third-party services like WebDAV, S3-compatible storage, or Resilio Sync instead of paying for official cloud sync.
Yes, SiYuan supports an English interface alongside Chinese and other languages.
SiYuan stores data locally by default and offers optional encrypted cloud sync, giving users control over where their data lives.
Like Obsidian, SiYuan is local-first and privacy-focused, but it uses native block-level references similar to Notion rather than page-only linking.