Best open-source alternatives to Notion

AFFiNE is an open-source workspace platform designed for writing, drawing, planning, and organizing knowledge in one place. It combines document editing and whiteboard-style canvas interactions, aiming to serve users who want a Notion- and Miro-like experience in a single product. The project emphasizes a local-first approach, so users keep data on their own devices while still getting real-time sync and collaboration across web and cross-platform clients. It also includes AI-assisted creation workflows, such as turning outlines into slides or summaries into mind maps, and supports self-hosting for teams or individuals who want more control over deployment and data.

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.

AFFiNE is an open-source workspace platform designed for people who want to combine note-taking, whiteboarding, planning, and knowledge management in one place. The README presents it as a local-first alternative to Notion and Miro, with emphasis on owning data on disk while still supporting cloud-based synchronization and collaboration. The project appears aimed at individuals and teams that need a flexible canvas for creative and structured work. It highlights an edgeless canvas where documents, tables, sticky notes, embedded web content, shapes, and slides can coexist, plus AI-assisted workflows for drafting reports, turning outlines into slides, summarizing content into mind maps, and prototyping ideas. It also mentions self-hosting and a plugin ecosystem, suggesting it is intended for users who want both a hosted product and the option to run and extend their own deployment.

AppFlowy is an open-source workspace application positioned as an alternative to Notion. It is designed for people who want a native, cross-platform productivity tool with stronger control over their data, and it also targets enterprises and builders who want to customize or extend the platform. The project combines Flutter and Rust to provide desktop and mobile clients, with self-hosting support for teams that want to run their own instance. The README highlights collaboration-oriented workplace management, AI capabilities, templates, databases, and documentation-style content, while emphasizing privacy, extensibility, and a community-driven approach to building productivity tools.

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.

Karakeep is a self-hostable bookmarking and read-it-later application for people who collect links, notes, images, and documents in one place. It is aimed at data hoarders and users who want a private alternative to cloud bookmark managers, with support for both individual capture and collaborative lists. The project combines browser extensions, mobile apps, and a web interface to make saving content easy across devices. It adds automation on top of bookmarking, including fetching metadata from links, OCR for images, RSS ingestion, page archiving, video archiving, semantic search, and AI-driven tagging and summarization. The README also mentions SSO support, a REST API, multiple clients, and a managed cloud offering for users who do not want to self-host.

Wiki.js is an open source wiki application designed for creating and managing documentation sites. It is positioned as a modern, lightweight, and powerful solution built on Node.js, making it suitable for teams or individuals who want a self-hosted knowledge base or wiki platform. The README highlights official documentation, installation and requirements pages, and a live demo, indicating that the project is intended to be deployed and configured by users rather than used as a hosted SaaS product. It also points to community support channels, translations, and sponsorship information, suggesting an active ecosystem around the core wiki software.

Trilium Notes is a cross-platform note-taking application aimed at people who want to build and manage large personal knowledge bases. It organizes content into deep hierarchical trees and supports placing a note in multiple locations, which makes it useful for structuring related information without duplicating it. The project positions itself as free and open source, with desktop, browser, and mobile access options. The application combines a rich editor, code note support, search, versioning, encryption, scripting, and visual note types such as maps and canvas sketches. It also supports synchronization through a self-hosted server, sharing notes publicly, and automation through a REST API. The README mentions OpenID and TOTP-based login, a mobile frontend, and third-party Android/iOS clients for offline use and server sync.

Etherpad is a web-based collaborative editor designed for real-time shared writing. It is intended for self-hosting on a user's own server and is described as scalable to thousands of simultaneous users. The project emphasizes extensibility through a plugin framework, allowing administrators to add features such as Markdown support, comments, hyperlinks, WebRTC-related enhancements, and custom authentication flows. The software is aimed at teams or organizations that need a lightweight, highly customizable pad system with strong data portability. It includes an administrative interface for plugin management, supports multiple instances from one installation via separate settings files, and exposes an HTTP API with OpenAPI definitions for integration into other web applications. The README also highlights localization support and skin customization for tailoring the user experience.

linkding is a self-hosted bookmark manager for people who want a lightweight way to organize and access saved links. It is aimed at users who prefer a minimal interface and straightforward setup, especially for hosting on their own server. The project centers on bookmark organization with tags, notes, read-later handling, and sharing. It also includes conveniences such as automatic metadata fetching for bookmarked sites, archiving to local HTML or the Internet Archive, browser extensions, a bookmarklet, and a PWA. For administrators and integrators, it provides an admin panel and a REST API, and it supports SSO through OIDC or authentication proxies.