# Vellum

> Vellum is a free, private notes app that runs entirely in the web browser at https://vellum.today. Write, keep files and photos, find anything (including text inside PDFs and, opt-in, scans and photos), and ask an optional on-device AI assistant that answers from your notes with sources. No account, no server that stores notes, no tracking; it works offline as an installable web app. When you want to go further, notes can run code cells in 25 languages, draw charts, and open Jupyter notebooks.

## Everyday use

- Notes: notebooks, links between notes ([[wikilinks]] and backlinks), tags, pinning, version history, a graph view, daily notes and templates.
- Files and photos: attach PDFs, Word documents, slides and images. Their text is searchable; text recognition for scans and photos is opt-in and runs on the device (about 15 MB, downloaded once from Vellum).
- Ask your notes: an assistant that is off by default. When turned on, a language model downloads once and runs in the browser (WebGPU, or a smaller CPU model). It answers across all notes, a notebook or one note, with numbered citations to the notes it used. Notes are never sent to a server.
- Phones: works in the phone's browser and can be added to the home screen.

## Privacy

- Notes, files, the search index and assistant conversations stay in the browser's private storage (Origin Private File System) on the device.
- Network use only when the user chooses: the AI model and text-recognition downloads after opting in, code-cell requests the user approves per note, and encrypted sync files written to the user's folder. Vellum's servers only deliver the app and its code runtimes.
- Sync: end-to-end encrypted (AES-256-GCM, passphrase) through a folder the user already syncs (iCloud Drive, Dropbox, OneDrive, Syncthing). No Vellum server. Needs Chrome or Edge on a desktop; elsewhere, backups move notes between devices.
- Clearing the browser's site data deletes the notes; users should keep a backup or set up sync.

## Going further

- Code cells: fenced code blocks run in place, in a sandbox on the device, as a notebook (a Jupyter alternative inside your notes). Languages: JavaScript, TypeScript, Python, SQL, Lua, Shell (emulated), Ruby, PHP, R, Perl, Go, Rust, C, C++, OCaml, Haskell, Zig, C#, F#, Java, Clojure, Elixir, Erlang, Scheme, Prolog. Each runtime downloads the first time it is used, then works offline. Outputs, tables and charts are saved with the note; cells can share data across languages; cells have no network access unless the user allows it for that note.
- The assistant can explain and fix code cells, and write and run code itself once the user approves it.
- Charts: interactive Plotly and Vega-Lite charts from Python and JavaScript cells, rendered offline.
- Import and export: Markdown files, Obsidian vaults and Jupyter notebooks in; Markdown, HTML, .ipynb, an Obsidian-compatible .zip and full backups out. A note can be shared as one self-contained .html page that anyone can open and run.

## Requirements

- A current browser with the Origin Private File System (Chrome, Edge, Firefox or Safari); developed and tested in Chrome.
- The assistant is fastest with WebGPU. Sync needs Chrome or Edge on a desktop.
- Price: free. No account.

## Links

- App: https://vellum.today/ (opens the app; first-time visitors see a short introduction)
- Introduction page: https://vellum.today/?welcome