SiYuan

Key features

• Every paragraph, list, document page, and embed is a content block with block-level references and two-way links, so notes connect at a finer grain than page links. Backlinks, mentions, and a global relationship graph surface those connections.[1][2]

• The editor is Markdown WYSIWYG with list outlines, block zoom-in focus, and large-document handling the project describes as smooth into the millions of words. Formulas, charts, flowcharts, Gantt and timing diagrams, staves, web clipping, and PDF annotation links extend it beyond prose.[1][2]

• Databases support table views with relations, rollups, and templates, so structured collections can link to each other instead of living in isolated pages.[1][2]

• Built-in flashcards use the FSRS spaced-repetition algorithm to schedule reviews, making study decks a first-class citizen rather than a plugin.[1][2]

• Multi-device sync is end-to-end encrypted with a user-held data-repo key. The paid subscription adds official cloud sync with 8GB of storage, and paid tiers can sync and back up through third-party S3 or WebDAV storage.[1][2][3]

• AI writing and Q/A chat work through an OpenAI API connection for drafting, translation, summarising, and grammar correction, and Tesseract OCR extracts text from images.[1][2]

• SiYuan runs on Windows, macOS, Linux, Android, iOS, and HarmonyOS with a Docker image for server self-hosting, publishes an HTTP API, and offers templates, JavaScript and CSS snippets, and a community marketplace of plugins, themes, and widgets.[1][2]

Who will love it

• Note-takers who think in linked ideas rather than folders will like block references, backlinks, and the graph. This is an editorial inference from the documented block model, not a vendor promise about any specific workflow.[1][2]

• Students and researchers combining notes with memorisation get flashcards, PDF annotation links, and databases in one workspace. This reads the documented feature set as a study workflow, which the vendor does not specifically prescribe.[1][2]

• Privacy-minded individuals who want Markdown notes on their own devices, with optional self-hosted Docker sync instead of a vendor cloud, match the local-first design. Paid sync is still required for the official cloud path.[1][2]

Who should pause

• Sync, cloud backup, and cloud storage are paid capabilities: local use is free, but official sync needs the subscription and third-party S3 or WebDAV sync needs a paid tier plus storage you buy and configure yourself. Official cloud storage is capped at 8GB per user.[1][2]

• Do not point a third-party folder-sync disk at the workspace; the project states this is unsupported and data may be corrupted. The supported paths are official sync or the documented S3 and WebDAV integrations.[1]

• The Docker server deployment is browser-only: it does not accept desktop or mobile app connections and offers no PDF, HTML, or Word export and no Markdown file import. Desktop and mobile clients are needed for the full experience.[1]

Alternatives and compatibility