Best open-source alternatives to Microsoft OneNote

Memos is an open-source, self-hosted note-taking application designed for quick capture and lightweight personal knowledge management. It is aimed at users who want a simple, timeline-first interface for creating Markdown notes without the overhead of folders or complex organization. The project emphasizes portability and self-hosting: notes are stored in Markdown, the app can be deployed with a single Go binary or via Docker, and it supports SQLite, MySQL, and PostgreSQL. It also presents itself as extensible through documented REST and gRPC APIs, making it suitable for integrations and custom workflows.

Joplin is an open source note-taking and to-do application for people who want to organize a large number of notes across devices. It stores notes in Markdown, supports notebooks, tagging, search, and editing from the app or an external text editor, making it suitable for users who prefer flexible, plain-text note workflows. The project is designed as an offline-first application, so users can access their notes even without internet connectivity. When synchronization is desired, Joplin can securely sync data with cloud services such as Nextcloud, Dropbox, OneDrive, or Joplin Cloud using end-to-end encryption. It also extends into browser-based clipping via its Web Clipper and can be customized with plugins and themes.

SiYuan is a personal knowledge management system designed around privacy and local control. It targets individuals who want to organize notes and knowledge using block-based editing, fine-grained references, and a Markdown-based WYSIWYG workflow rather than a traditional document-only model. The project emphasizes a broad feature set that includes large-document editing, databases, flashcards, export options, snippets, OCR, and an API for extension and integration. It also has a wider ecosystem of companion apps and components for mobile, desktop, marketplace content, and data repositories, suggesting it is aimed at users who want a cross-platform knowledge workspace with both local and deployment-oriented options.

Logseq is an open-source knowledge management and collaboration platform aimed at people who want a privacy-focused way to organize notes, tasks, and related information. It supports common note formats such as Markdown and Org-mode, and it emphasizes user control, longevity, and extensibility through plugins and themes. The README presents Logseq as suitable for students, professionals, and anyone managing personal or team knowledge workflows. It is available as a desktop application, has a web version for testing the DB version, and includes mobile apps. The DB version adds graph-based data, a new sync approach called RTC for real-time collaboration, and automated or SQLite database backup guidance because the feature set is still in beta/alpha.

Trilium Notes is a cross-platform note-taking application aimed at people who want to organize large personal knowledge bases in a deeply structured way. It presents notes as a hierarchical tree, supports cloning notes into multiple places, and includes tools for navigation, search, and advanced organization through note attributes and scripting. The project also provides a web interface, mobile access through a server installation, synchronization with a self-hosted sync server, and sharing/publishing notes to the public internet. It is designed for users who want a capable personal knowledge base system with rich editing, encryption, automation, and extensibility, while still being usable as a desktop app or via the browser.

Blinko is a self-hosted, AI-assisted note-taking project aimed at people who want to capture ideas quickly and organize them for later retrieval. It presents itself as a lightweight card-based notes app that emphasizes speed, privacy, and convenience for individual users. The project’s core functionality centers on storing notes in the user’s own environment while adding AI-powered retrieval through RAG-style natural-language search. The README highlights Markdown support, plain-text capture, and native support for multiple platforms through Tauri, including macOS, Windows, Android, and Linux. It is distributed with a Docker-based install path and is positioned as an open-source project that welcomes community contributions.

TiddlyWiki is a personal web notebook and interactive wiki designed for people who want a flexible, self-contained place to store and organize information. It can be used as a single HTML file in the browser, which makes it portable and easy to keep for long-term use, or as a Node.js application for more advanced client/server setups. The project is aimed at users who want a highly customizable note-taking and knowledge-management tool, as well as developers who want to extend or adapt the interface. Its UI is built in WikiText, allowing the whole application to be modified in a hackable way. The README also points users to a live demo, community forums, and developer documentation.

Standard Notes is an encrypted note-taking application aimed at people who want a secure, durable place to store notes, files, and other important writing. It emphasizes privacy through end-to-end encryption and cross-device sync, and it presents itself as suitable for both personal use and professional workflows. The project also supports self-hosting and a web-based deployment path, allowing users to run the web app from static files behind their own server. Beyond note taking, it includes publishing capabilities through Listed and supports third-party extensions/plugins, making it more than a basic notes app. The README positions it as a platform for long-term, private writing and publishing rather than just a simple editor.

SilverBullet is a self-hosted personal knowledge management platform aimed at users who want a browser-based workspace for notes, writing, and lightweight knowledge organization. It presents content as Markdown pages in a “Space,” and combines note-taking with wiki-style linking, outlining, task management, and simple database-like objects and queries. The project is especially suited to people who want more than a static markdown editor: it includes a programmable layer based on Lua for generating content and building custom commands, templates, and widgets. The README also indicates that SilverBullet has both a frontend and backend, with the client written in TypeScript and the server in Go, and it can be built and run locally or packaged into a Docker container.

flatnotes is a self-hosted note-taking web app aimed at users who want a simple, distraction-free way to manage markdown notes. It avoids a traditional database and instead stores content directly as files in a folder, which makes the notes portable and easy to edit outside the app. The project focuses on a clean interface with features such as search, tagging, markdown editing, wikilinks, and theme customization. It is designed for people who want a lightweight personal knowledge base that can be run locally or self-hosted, with support for several authentication modes and a REST API for integration.