Libby Downloader

Download audiobooks from Libby to your computer for offline listening.

Features

• One-Click Downloads: Chrome extension downloads audiobooks directly from Libby
• MP3 Tagging: CLI adds title, author, narrator, and cover art to downloaded files
• M4B Audiobooks: Merge chapters into a single audiobook file with chapter markers

Setup

git clone https://github.com/pdugan20/libby-downloader.git
cd libby-downloader
npm install
npm run build:extension

Load the extension in Chrome:

1. Navigate to chrome://extensions/
2. Enable "Developer mode" (top-right toggle)
3. Click "Load unpacked" and select the chrome-extension folder

To use the CLI (optional):

npm run build && npm link

Usage

Downloading

Open an audiobook in Libby, then click the download button in the top-right navigation bar. Files save to ~/Downloads/libby-downloads/[Book Title]/.

CLI

The CLI provides tagging and merging for downloaded books. Run libby for the interactive menu, or use commands directly:

libby                      # Interactive menu
libby list                 # List all downloaded books
libby tag                  # Tag MP3 files with metadata (interactive)
libby tag ~/path/to/book/  # Tag a specific folder
libby merge                # Merge chapters into M4B audiobook (interactive)
libby merge ~/path/to/book/

Options:

• --data-dir <path> — Override the downloads directory
• --title, --author, --narrator, --cover-url — Override tag metadata
• --verbose — Enable debug logging

Development

npm run build              # Build CLI and extension
npm run dev -- list        # Run CLI without building
npm run dev:extension      # Watch mode for extension
npm run check-all          # Full validation (typecheck, lint, format, test)
npm test                   # Run unit tests
npm run test:cli           # Run CLI integration tests against fixtures

See docs/architecture.md for system design and docs/releasing.md for the release process.

Disclaimer

This tool is for educational purposes only. Users are responsible for complying with their library's terms of service and respecting copyright agreements.