Lanternote

Lanternote

A fast, private desktop app for very large folders of Markdown notes.

Read, edit, search, query and map 200,000 notes on Windows, macOS or Linux — no account, no cloud, no graphics card needed.

Download · Features · Performance · User guide · Build from source · Changelog

20 seconds on a made-up folder of 139,434 notes: quick open · full-text search · Command Center · galaxy · link graph

Why Lanternote

• Built for size. Tested on a real library of 190,000+ notes and 2.5 million links: it reopens in 1–2 seconds and searches in milliseconds.
• Runs on any PC. The link graph and the galaxy are drawn without a graphics card. Portable: one .exe, no installation, no admin rights.
• Your files stay yours. Plain .md files in a folder you choose. Nothing is uploaded, nothing phones home, everything works offline.
• More than a reader. Live queries, task lists, calendars, Kanban boards, canvases and a Command Center page — all stored as ordinary Markdown.
• Works with your AI assistant. Claude and other MCP assistants can search and, if you allow it, edit your notes — every AI change keeps the old text.

Features

Command Center

One page with what matters today — projects, due dates, open tasks, a calendar, recent notes. It is built from an ordinary note you can edit.

Your notes as a galaxy

Every star is a note, every arm a folder, and notes you edited this week shine. Zoom in to read names, click a star to open it.

Link graph on any PC

The Map engine lays out hundreds of thousands of notes once, in the background, and draws them like a digital map — no GPU required. A Live GPU engine is there when you have one.

Editing that protects your work

Live preview (Markdown marks hide away from the cursor; checkboxes, pictures and links work as you write), tabs, and a right pane to read one note while you write another. Auto-save, per-note undo, [[ and # completion, paste images, rename with link updates, and version history. If a file changes on disk while you edit, you choose which version to keep.

Search everything, instantly

Full-text search across every note, accent-insensitive: "exact phrases", -exclusions, OR, path:, title:, tag: — and *1133 finds a fragment inside a word or a part number. Quick open (Ctrl+O) finds any note by name as you type.

Live queries

Tables, lists, task lists and month calendars from dataview ` blocks, written in the Dataview query language — refreshed as your notes change.

Tasks and calendars

Collect tasks from every note, sort them by due date and tick them right in the results — the note is updated on the spot.

Kanban boards

Drag cards between lanes. Boards are plain Markdown notes in the common board format, so they stay readable anywhere.

Read without leaving the page

Point at a link to preview the note (or just the heading it points to) in a card you can scroll and click in. Footnotes jump to their text and back; bookmarks keep the notes you use most above the file list.

Unlinked mentions

See every note that writes this note's name — or one of its aliases — without linking it, and turn a mention into a link in one click, keeping the words as written.

Canvas

Lay out notes, text and links on an infinite board. Canvases use the open JSON Canvas format.

Connect an AI assistant

Built-in MCP server: search, read, run queries, list tasks, check a quotation and its numbers against the note before citing it (verify_quote) and — only if you allow it — write. Limit it to chosen folders; every change is logged and reversible. For Claude Desktop, just double-click lanternote- .mcpb from the release.

Also included: wiki links with headings, blocks and aliases · footnotes · folding of headings, lists and code in the editor · embeds (![[note]], images, audio, video) · backlinks and outline · front-matter properties · tags and nested tags · callouts · highlights and comments · Mermaid diagrams · note templates · daily notes · image viewer · command palette · print to PDF · light and dark themes.

Performance

Measured on a real-world library of 190,522 notes, 2.49 million links (728 MB), and on a made-up 139,000-note folder used for all pictures in this README.

How it stays fast

• A worker thread owns the index (indexer.js): it reads and parses every note, keeps a compact search index (accent-insensitive, 50 MB for the library above) and answers searches and queries. The window only holds a small index — paths plus a Uint32Array of links — and reads a note's text when you open it.
• Disk cache (index-cache): parsed notes and the resolved link graph are cached, so a reopen shows the folder at once and only stats files in the background.
• Incremental updates: editing, adding or deleting a file re-reads only that file. Changes made by other apps or by sync tools appear within about a second.
• Graph "Map" engine (layout-worker.js, src/atlas.js): the layout is computed once (Pivot MDS plus neighbour smoothing) and cached; drawing uses level of detail on a 2D canvas, so an idle graph costs no CPU.
• Graph "Live" engine: cosmos.gl runs both the force layout and the drawing on the GPU. Links of "hub" notes with more than 1,000 links are hidden by default — one note with 72,000 backlinks alone drops the frame rate from ~120 to ~19 FPS.
• Limits: 1,000,000 files; up to 1.5 GB of text kept for search (beyond that, search covers part of the folder and says so).

Download

Get the file for your system from the latest release:

Then click Open a folder and choose your notes. Next time Lanternote reopens the same folder and note.

Only want your AI assistant to read your notes? Download lanternote- .mcpb from the same release and double-click it: Claude Desktop installs the extension and asks for your notes folder. It is read-only unless you turn on *Let the AI edit notes*, and it works on Windows, macOS and Linux.

[!NOTE]

The app is not code-signed yet, so your system may warn you the first time:

- Windows SmartScreen: More info → Run anyway.

- macOS: right-click Lanternote.app → Open → Open. If macOS says the app "is damaged", run xattr -cr /Applications/Lanternote.app once.

- Linux: on Ubuntu 24.04 and later, if the AppImage does not start, run it with --no-sandbox.

The macOS and Linux builds are new: every feature is tested on both systems by CI, but please report anything that looks wrong.

Settings, the index cache and recovery copies are kept on each computer (%APPDATA%\Lanternote on Windows).

Press F1 in the app for the built-in guide, or read the illustrated user guide.

Keyboard shortcuts

Privacy

Lanternote reads and writes only the folder you open and its own settings folder. It has no account, no telemetry and no update check; all libraries are bundled, so it runs without a network connection. Pictures linked from the internet () are not fetched unless you click one or turn on Settings → Files & links → Load pictures from the internet, since fetching them tells the web server when a note is opened. Pictures a note links on this PC outside the folder () are shown, and links to documents there (PDF, picture, text) open in their own app; only those file types are read or opened that way, never a program, and Settings → Files & links can turn it off.

The only exception is one you turn on yourself: when you connect an AI assistant, the notes it reads are sent to that assistant's provider. You can make the connection read-only and limit it to chosen folders.

Build from source

Requires Node.js 22 or later and Git. Build outside folders synced by OneDrive or Dropbox — node_modules and the builds are large.

git clone https://github.com/ericthai-labs/lanternote.git

cd lanternote npm ci # installs dependencies and bundles the editor into src/ven