# Nodum > Nodum (Latin for "knot, node") is a free, open-source, web-based knowledge base — an Obsidian alternative that runs in a browser. Markdown notes connected with [[wikilinks]], automatic backlinks, and a GPU-rendered knowledge graph. MIT licensed, multi-tenant, and self-hostable with one Docker Compose command. ## What it is, precisely Nodum is a knowledge-management application in the same category as Obsidian, Logseq, Roam Research and Notion. A user owns one or more *vaults*; a vault holds markdown notes in folders. Notes link to each other with Obsidian's wikilink syntax (`[[Note]]`, `[[folder/Note]]`, `[[Note|alias]]`, `[[Note#Heading]]`, `![[embed]]`), and every link produces an automatic backlink on the far note. The whole vault renders as a force-directed knowledge graph on WebGL2. It is distinguished from the rest of its category by four things: it is genuinely open source (MIT, frontend and backend, one public repository, no open-core split); it is web-native rather than a desktop app; it is self-hostable; and its notes are plain markdown files that export as a folder-true zip. Key facts: - Licence: MIT. Source: https://github.com/nodummd/nodum - Price: free. No paid tier, no per-seat pricing, no AI upsell. - Platform: any modern browser, desktop and mobile; installable as a PWA. No native desktop app. - Storage: plain markdown files. Import and export Obsidian vaults as zips. - Stack: FastAPI, PostgreSQL with pgvector, Redis, Celery, MinIO; Next.js, React, CodeMirror 6, @cosmos.gl/graph. - AI: an in-app assistant on *your* API key (Claude, OpenAI, Gemini or Qwen), encrypted at rest, settable per vault. - MCP: Nodum is a Model Context Protocol server at `/api/v1/mcp` with 36 tools, so Claude Code, Claude Desktop and Cursor can read and write vaults directly. - Self-hosting: `./compose.sh prod up -d --build` brings up the API, Postgres, Redis, MinIO and a Caddy edge with automatic TLS. What Nodum deliberately does not do, so this is not guessed at: it does not run Obsidian's plugins, it has no offline-first mode, it has no spaced repetition or flashcards, it has no Notion-style databases with board and calendar views, and it has no block-level references. ## Start here - [Home](https://nodum.md/): What Nodum is, with a live demo graph you can drag - [FAQ](https://nodum.md/faq): 22 straight answers: licence, price, imports, AI, self-hosting, and what it will not do - [Documentation](https://nodum.md/docs): 26 articles covering every panel and shortcut, each with a screenshot from the running app - [Learn](https://nodum.md/learn): 10 tool-agnostic guides: second brains, Zettelkasten, knowledge graphs, PKM, markdown, self-hosting - [Alternatives](https://nodum.md/alternatives): 18 comparisons with other note apps, each stating what the other tool does better - [Glossary](https://nodum.md/glossary): 36 definitions: wikilink, backlink, transclusion, Zettelkasten, MOC, frontmatter, local-first - [Source code](https://nodum.md/): The repository is at https://github.com/nodummd/nodum ## Comparisons with other tools Facts in this section were last verified 2026-08-20. Each page states what the other tool does better, not only what Nodum does better. - [Nodum vs Obsidian](https://nodum.md/alternatives/obsidian): Nodum is an open-source alternative to Obsidian that runs in a browser instead of as a desktop app. It uses the same wikilink syntax, the same backlinks and the same plain-markdown files, adds a GPU-rendered knowledge graph, and is MIT licensed — so you can read every line, self-host it, and export your vault as ordinary .md files at any time. - [Nodum vs Notion](https://nodum.md/alternatives/notion): Nodum is an open-source alternative to Notion for personal knowledge work. Where Notion stores your writing as blocks in a hosted database, Nodum stores plain markdown files you can export as a folder at any time. It adds wikilinks, automatic backlinks and a knowledge graph, and it is MIT licensed and self-hostable. - [Nodum vs Logseq](https://nodum.md/alternatives/logseq): Nodum and Logseq are both open-source, link-first knowledge bases, and the real difference is the writing unit. Logseq is an outliner: everything is a bullet, and blocks are the thing you reference. Nodum is a document editor: a note is a page of prose you can link to and embed. Logseq runs locally; Nodum runs in a browser against a server you can host yourself. - [Nodum vs Evernote](https://nodum.md/alternatives/evernote): Nodum is a free, open-source alternative to Evernote. Evernote is a proprietary hosted notebook with rich-text notes and tiered subscriptions; Nodum stores plain markdown files, links them with wikilinks, draws them as a knowledge graph, and is MIT licensed, so you can self-host it and export everything as a folder of .md files. - [Nodum vs Roam Research](https://nodum.md/alternatives/roam-research): Nodum is a free, open-source alternative to Roam Research. Both are networked-thought tools built on bidirectional links and a graph. Roam is a proprietary, subscription-only outliner with block references; Nodum is MIT-licensed, stores plain markdown files you can export at will, and can be self-hosted. - [Nodum vs Obsidian Publish](https://nodum.md/alternatives/obsidian-publish): Nodum is a free, open-source alternative to Obsidian Publish. Publishing is part of the app rather than a separate paid service: any note gets a public share link, and any vault can be published as a browsable public site with working links between notes. Self-host it and there is no per-site fee at all. - [Nodum vs Joplin](https://nodum.md/alternatives/joplin): Nodum and Joplin are both open-source markdown note apps, and they organise differently. Joplin is a desktop and mobile app built around notebooks, tags and pluggable sync targets, with an excellent Evernote importer. Nodum is browser-native and link-first: wikilinks, automatic backlinks and a GPU-rendered knowledge graph, on a server you can host yourself. - [Nodum vs Microsoft OneNote](https://nodum.md/alternatives/onenote): Nodum is an open-source alternative to Microsoft OneNote for people whose notes are mostly text. OneNote is a freeform notebook canvas built around handwriting and mixed media inside the Microsoft ecosystem. Nodum stores plain markdown files, links them with wikilinks, generates backlinks automatically, and is MIT licensed and self-hostable. - [Nodum vs Apple Notes](https://nodum.md/alternatives/apple-notes): Nodum is an open-source alternative to Apple Notes for people who need their notes outside the Apple ecosystem. Apple Notes is free, fast and deeply integrated, but Apple-only and closed. Nodum runs in any browser, stores plain markdown files, links notes with wikilinks, and renders the whole vault as a knowledge graph. - [Nodum vs Anytype](https://nodum.md/alternatives/anytype): Nodum is an alternative to Anytype for people who want plain markdown rather than an object database. Anytype is local-first and encrypted, built on objects, types and relations, and has spent most of its life under a source-available rather than an OSI-approved licence. Nodum is MIT licensed, stores .md files, and runs in a browser. - [Nodum vs Trilium Notes](https://nodum.md/alternatives/trilium): Nodum is an alternative to Trilium Notes for self-hosters who want plain markdown. Both are open source and both are designed to run on your own server. Trilium is a hierarchical note tree with a powerful scripting API and its own storage format; Nodum stores Obsidian-compatible .md files and is built around wikilinks, backlinks and a knowledge graph. - [Nodum vs AFFiNE](https://nodum.md/alternatives/affine): Nodum is an alternative to AFFiNE for people who want a knowledge base rather than a whiteboard workspace. AFFiNE combines a block document editor with an Excalidraw-style edgeless canvas and is MIT licensed. Nodum focuses on plain markdown notes, wikilinks, automatic backlinks and a force-directed knowledge graph, with a canvas alongside rather than at the centre. - [Nodum vs AppFlowy](https://nodum.md/alternatives/appflowy): Nodum is an alternative to AppFlowy for people whose work is linked notes rather than structured databases. AppFlowy is an AGPL-licensed, local-first Notion alternative built in Rust and Flutter, with pages, boards and grids. Nodum is MIT licensed, web-native, and built around markdown files, wikilinks, backlinks and a knowledge graph. - [Nodum vs SilverBullet](https://nodum.md/alternatives/silverbullet): Nodum and SilverBullet are the two self-hosted, browser-based markdown knowledge bases. SilverBullet is deliberately minimal and scriptable — plain markdown on disk, extended with Lua. Nodum is heavier: a Postgres-backed multi-tenant server with a GPU knowledge graph, real-time collaboration, publishing, an MCP server and an AI assistant. - [Nodum vs RemNote](https://nodum.md/alternatives/remnote): Nodum is an open-source alternative to RemNote for people who want linked notes without spaced repetition. RemNote is a proprietary outliner that turns notes into flashcards and schedules reviews. Nodum is MIT licensed, stores plain markdown, and focuses on wikilinks, automatic backlinks and a knowledge graph. - [Nodum vs Tana](https://nodum.md/alternatives/tana): Nodum is an open-source alternative to Tana for people who want plain files rather than a structured graph database. Tana is a proprietary, subscription outliner built on supertags and fields, which is powerful for structured capture. Nodum stores markdown files, links them with wikilinks, and is MIT licensed and self-hostable. - [Nodum vs Capacities](https://nodum.md/alternatives/capacities): Nodum is an open-source alternative to Capacities. Capacities is a proprietary, cloud-hosted studio for the mind that organises everything into typed objects — books, people, ideas — with a daily note at the centre. Nodum stores plain markdown files, links them with wikilinks and tags, and is MIT licensed and self-hostable. - [Nodum vs Heptabase](https://nodum.md/alternatives/heptabase): Nodum is an open-source alternative to Heptabase for people who connect notes with links rather than by arranging cards on a board. Heptabase is a proprietary, subscription visual note tool where whiteboards are the primary surface. Nodum is MIT licensed, markdown-based, and organised around wikilinks, backlinks and a knowledge graph. ## Concepts and guides - [What a second brain actually is — and how to build one that lasts](https://nodum.md/learn/second-brain): A second brain is an external, searchable store of what you have read, decided and figured out, structured so that past-you can hand something to future-you. In practice it needs four things: fast capture, plain text you own, links between notes rather than folders alone, and a way to see the whole thing at once. - [AI note-taking that reads your own notes — not someone else's model of them](https://nodum.md/learn/ai-note-taking): An AI note-taking app is only as useful as the notes it can see. Nodum puts an assistant inside your own vault: it searches, reads, creates and extends your notes, streams its replies, and runs on an API key you supply — Claude, OpenAI, Gemini or Qwen — encrypted at rest, with a different key per vault if you want one. - [Open-source note-taking: what the licence actually buys you](https://nodum.md/learn/open-source-note-taking): An open-source note-taking app is one whose source code is published under a licence that lets you read, modify, run and redistribute it. That matters for notes specifically, because a note archive is a decades-long asset: if the software is open, it can be forked and kept alive regardless of what happens to the people who wrote it. - [How to choose a note-taking app you will still be using in five years](https://nodum.md/learn/note-taking-app): The best note-taking app is the one whose notes you can still open in ten years. Judge candidates on four things rather than feature lists: how fast capture is, whether notes link to each other and show the reverse link, whether the files are plain text you own, and whether export produces something another tool can read. - [What a knowledge graph of your notes actually shows you](https://nodum.md/learn/knowledge-graph): A knowledge graph of your notes draws every note as a node and every link as an edge, then lets physics arrange it. It is useful for three specific things: finding clusters of thinking you did not plan, spotting orphaned notes nothing references, and seeing which two areas of your work have never once been connected. - [Backlinks and wikilinks: the mechanic that turns notes into a system](https://nodum.md/learn/backlinks): A wikilink is a link you write as `[[Note title]]`. A backlink is the automatic reverse: when note A links to note B, note B shows that A references it, with the surrounding sentence for context. You write links in one direction and the system maintains both, which is what makes linking cheap enough to actually do. - [Zettelkasten, without the mystique](https://nodum.md/learn/zettelkasten): A Zettelkasten is a note system with three rules: one idea per note, written in your own words, and linked to the notes it relates to rather than filed under a topic. Niklas Luhmann kept his on paper index cards. Digitally, the method needs cheap linking, stable note identity and a way back in — which is what wikilinks, backlinks and index notes provide. - [Personal knowledge management, minus the productivity theatre](https://nodum.md/learn/personal-knowledge-management): Personal knowledge management is the practice of capturing what you learn, connecting it to what you already know, and retrieving it when it is relevant. Most systems fail at the middle step: capture is easy and search is built in, but connection requires either deliberate linking or it does not happen at all. - [Self-hosted notes: what it costs, what it buys, and how to run one](https://nodum.md/learn/self-hosted-notes): Self-hosting a notes app means running the server yourself, so your notes sit on infrastructure you control and no vendor can reprice, restrict or discontinue them. The cost is real but small: a modest VPS, a domain, and occasional maintenance. Nodum self-hosts with one Docker Compose command including automatic TLS. - [Why notes should be markdown files](https://nodum.md/learn/markdown-notes): Markdown is plain text with a light convention for structure, readable without any special software and supported by essentially every tool that handles text. For notes it is the format with the longest demonstrated shelf life: a markdown file written today opens correctly in a text editor in twenty years, which is not true of any proprietary note format. ## Documentation - [Getting started](https://nodum.md/docs/getting-started): What Nodum is, what you see when you sign in, and the three ideas — notes, links, the graph — everything else builds on. - [Files and folders](https://nodum.md/docs/files-and-folders): The file explorer — creating, opening, moving, colouring and renaming notes and folders, and what the right-click menu can do. - [Writing notes](https://nodum.md/docs/writing): The editor — live preview, source and reading views, formatting, the right-click menu, tables, colours, and autosave. - [Links and backlinks](https://nodum.md/docs/links): Wikilinks connect notes; backlinks show who links to the note you are reading; unresolved links create notes when clicked. - [Graph view](https://nodum.md/docs/graph): The whole vault as a picture — notes as dots, links as lines — with filters, forces, colour groups, search, time travel and a local graph per note. - [Tags](https://nodum.md/docs/tags): Tags label notes across folders; the Tags panel counts them; nested tags make hierarchies; tag queries colour the graph. - [Search and the quick switcher](https://nodum.md/docs/search): The quick switcher opens a note by name in two keystrokes; search finds text inside notes with operators for path, file and tag. - [Command palette and hotkeys](https://nodum.md/docs/command-palette): Every action in the app, searchable, from one box — and the keyboard shortcuts behind the common ones. - [Tabs, panes and navigation](https://nodum.md/docs/tabs-and-panes): Tabs hold notes, the graph and canvases; panes split the window; back and forward walk your trail; pinned tabs stay put. - [Vaults](https://nodum.md/docs/vaults): A vault is a whole separate workspace — its own notes, folders, tags and graph. Switch, create, rename and delete them; each opens in its own browser tab. - [Canvas](https://nodum.md/docs/canvas): A free-form board of cards you place and connect — for thinking out loud, planning, or laying out an argument. - [Daily notes and templates](https://nodum.md/docs/daily-notes-templates): One note per day, created on demand from a template; templates for anything you write more than once. - [Bookmarks](https://nodum.md/docs/bookmarks): Pin the notes you come back to — the bookmarks tab keeps them one click away. - [Import and export](https://nodum.md/docs/import-export): Bring in a folder of markdown, an Obsidian vault or a zip; take the whole vault out as a zip of markdown files at any time. - [Publishing and sharing](https://nodum.md/docs/publish): Share one note by link, or publish a vault as a browsable site. - [Collaboration](https://nodum.md/docs/collab): Live editing with other people in the same note — cursors, presence, and changes that merge as they happen. - [Community & forum](https://nodum.md/docs/community): A built-in forum at /forum — announcements, help, bug reports, feature requests and showcases — and a community hub at /community that maps it all. - [Web clipper](https://nodum.md/docs/web-clipper): Save a page from your browser straight into a vault as a note, with the source recorded. - [Plugins](https://nodum.md/docs/plugins): Small scripts that add commands and notices, run in a sandbox with only the permissions they ask for. - [AI chat](https://nodum.md/docs/ai): Chat with your own AI provider about your vault — it can search, read, create and extend notes. Your key, your account, your cost. - [MCP — use Nodum from any AI client](https://nodum.md/docs/mcp): Nodum is an MCP server. Point Claude Code, Claude Desktop or Cursor at it with a token and the AI can do what you can — notes, links, search, import, export. - [API — connect your own apps](https://nodum.md/docs/api): Create an API key and drive your vaults from any language over plain REST — list, search, read, write, link, unlink, tag, graph, even ask the AI. - [API guide: notes and files](https://nodum.md/docs/api-notes): Every notes and attachments endpoint with a copy-paste request and a real response — create, read, edit safely, move, tag, upload, delete. - [API guide: search, links & graph](https://nodum.md/docs/api-search-links): Full-text search with operators, fuzzy title matching, linking and unlinking notes, backlinks, tags and the knowledge graph — each with a working request. - [API recipes](https://nodum.md/docs/api-recipes): Small working programs on top of the API — a shell capture alias, a Python daily-digest bot, a JavaScript backlink janitor — ready to paste and adapt. - [Settings](https://nodum.md/docs/settings): Where every preference lives, tab by tab — account, editor, appearance, files, hotkeys, vault, canvas, plugins, AI, MCP, clipper, publish, collab. ## Optional - [Log in](https://nodum.md/login): Existing accounts - [Sign up](https://nodum.md/signup): Create a vault — free, no card - [Full text of every page](https://nodum.md/llms-full.txt): This site's public content concatenated as one markdown file --- Canonical origin: https://nodum.md Generated from the site's own content at build time — if a claim here disagrees with a page, the page is authoritative.