Notesnook vs SiYuan

Notesnook is a note-taking app for web, Windows, macOS, Linux, iOS, and Android, with note sharing and offline access. Notes are encrypted end-to-end before leaving the device, and the apps and sync server are open source under GPLv3. The app can be locked with a fingerprint, PIN, or password; selected private notes can also have a separate password. Individual notes can be published as web pages, optionally password protected. Zapier, IFTTT, or a custom script can send notes through the Inbox API. The free plan offers unlimited notes on unlimited devices, 50 MB of attachment storage per month, files up to 10 MB, and limits of 50 notebooks and 50 tags. Free users can read web-clipped content offline; paid plans include full offline mode and provide from 1 GB to 25 GB of attachment storage per month. Monthly plan prices listed include Essential at $1.99 per month, Pro at $6.99 per month, and Believer at $8.99 per month, including tax. Subscriptions can be cancelled without fees, with notes remaining readable and exportable.

SiYuan is a personal knowledge management system for building a linked collection of notes. It supports Markdown, block-level references and bidirectional links, and organizes content into blocks with more than 20 block-level and more than 10 span-level element types. Backlinks can be filtered and searched; relationship graphs are available across a notebook and at block level. Databases support relations, rollups and templates, while flashcards use the FSRS spaced-repetition algorithm. Its AI feature connects to OpenAI for writing continuation, translation, summaries, brainstorming and grammar or spelling corrections. SiYuan supports offline access, and the maker describes multi-device synchronization as incremental and end-to-end encrypted. It is available on Windows, macOS, Linux, iOS, Android and the web, with a Chrome/Edge extension, API and Docker self-hosting. The maker says data stays under the user's control on their device. Free access is free; PRO Features is listed at $64 a month with lifetime-use wording, and Subscription at $148 a month with 8GB cloud storage.