reMarkable Sync - Calibre Plugin

A Calibre plugin for synchronizing e-books with reMarkable tablets (Paper Pro Move and other models) via the reMarkable desktop app.

Features

• Send books from Calibre library to reMarkable tablet
• Export selected books as reMarkable-tuned PDFs to any folder (no device required)
• Automatic EPUB to PDF conversion with configurable font, size, line height, and margins
• Device-specific page sizes (reMarkable 2, Paper Pro, Paper Pro Move)
• Full-bleed cover pages (no margins, optimized for e-ink display)
• Select destination folder on reMarkable
• Sync reading positions back to Calibre (progress, page, last read)
• Document naming: "Series-Number Title - Author" for easy organization

Platform support: Developed and tested on macOS. The plugin uses Calibre's cross-platform APIs and has code paths for Windows and Linux, but those are currently untested — feedback welcome.

How syncing works

This plugin does not talk to the reMarkable cloud or to the tablet directly. It writes books into the local storage of the reMarkable desktop app, which then uploads them to your tablet on its next sync.

That means you need to:

1. Have the reMarkable desktop app installed and logged in to your reMarkable account.
2. Quit and restart the reMarkable desktop app after sending books. The app only picks up new documents at startup; without a restart, nothing reaches the tablet.

Prerequisites

• Calibre 5.0.0 or later
• reMarkable desktop app installed and logged in (required — see above)
• Python 3 (bundled with Calibre)

Optional (for PDF page counting)

The plugin uses multiple fallback methods for PDF page detection. Install any of these for better reliability:

• poppler-utils (provides pdfinfo) - recommended
• PyPDF2 Python library
• pikepdf Python library
• qpdf command-line tool

Installation

1. Go to the latest release and download the remarkable_sync-X.Y.Z.zip asset under Assets.

   ⚠️ Do not download "Source code (zip)" or "Source code (tar.gz)". Those are auto-generated by GitHub, wrap everything inside a top-level folder, and Calibre will refuse to load them.

2. In Calibre, go to Preferences → Plugins → Load plugin from file and select the downloaded zip.

3. Restart Calibre. The plugin appears as reMarkable Sync in the toolbar and under Tools.

4. Open Tools → reMarkable Sync → Settings… to configure your default folder, device type, conversion preferences, and (optionally) custom columns for reading-position sync.

Example output

Curious what the conversion looks like before installing? See examples/the-time-machine.pdf — The Time Machine by H. G. Wells, sourced from Standard Ebooks and converted with the plugin's default settings for the reMarkable Paper Pro Move (full-bleed cover, configured typography and margins).

Development Setup

Project Structure

remarkable-sync/
├── __init__.py      # Plugin entry point (InterfaceActionBase)
├── ui.py            # Menu actions and user interface
├── main.py          # Book path utilities
├── worker.py        # Conversion and sending logic (runs in background)
├── remarkable.py    # reMarkable file format handling
├── config.py        # Settings UI and preferences
├── images/          # Plugin icons
└── Makefile         # Development commands

Installation for Development

# Using Makefile (macOS)
make install    # Install plugin
make run        # Launch Calibre
make dev        # Install + run

# Or directly with calibre-customize
calibre-customize -b .

After installation, restart Calibre to load the plugin.

Running with Debug Output

# macOS
/Applications/calibre.app/Contents/MacOS/calibre --debug

# Windows/Linux
calibre --debug

Debug output appears in the terminal, useful for troubleshooting plugin issues.

Development Workflow

1. Make changes to plugin source files
2. Run calibre-customize -b . to reinstall
3. Restart Calibre (or use the debug console to reload)
4. Test via Tools → reMarkable Sync → Send to reMarkable

Accessing Plugin Settings

Preferences → Plugins → User interface action → reMarkable Sync → Customize plugin

Available settings:

• Upload Settings
  • Default folder on reMarkable (with pinned folders marked 📌)
  • Device type (reMarkable 2, Paper Pro, Paper Pro Move) — controls the PDF page size
• PDF Conversion Settings
  • Auto-convert EPUB to PDF
  • Font family (any installed system font, or system default)
  • Base font size (px) — picked from a curated list (9–32 px)
  • Line height (100–200 %)
  • Page margins, in points: Left, Right, Top, Bottom (0–100 pt each)
• Sync Settings (optional, for syncing reading positions back to Calibre)
  • Custom-column mappings: reMarkable UUID, Progress (%), Current page, Last read
  • See Reading Position Sync below

Reading Position Sync

The plugin can sync reading positions from reMarkable back to Calibre using custom columns. This allows you to track your reading progress across your library.

Setting Up Custom Columns

Go to Preferences → Add your own columns and create the following columns:

Column	Type	Description	Required
reMarkable UUID	Text	Document ID for safe sync	✅ Required
Progress (%)	Floating point numbers	Reading progress on 0-100 scale (e.g., 45.2 = 45.2%)	Optional
Current page	Integers	Current page number (1-indexed)	Optional
Last read	Date	Timestamp of last reading session	Optional

How sync works:

• When you send a book to reMarkable, the plugin stores the document UUID in Calibre
• Only books with a UUID are synced (books sent from Calibre)
• Only documents in the configured reMarkable folder are considered
• If the existing "Last read" value is more recent than the reMarkable timestamp, no data will be overwritten

Integration with Reading Goal Plugin

If you use the Reading Goal plugin, you can share columns:

reMarkable Sync Column	Reading Goal Column
Progress (%)	Percent read
Last read	Status date

Current page cannot be shared as Reading Goal doesn't use it.

Using Reading Position Sync

1. Configure custom columns in Settings (UUID column is required)
2. Send books to reMarkable using Tools → reMarkable Sync → Send to reMarkable
3. Read on your reMarkable device
4. Click Tools → reMarkable Sync → Sync Reading Positions

Document Naming

Books sent to reMarkable are named using the format: Series-Number Title - Author

Examples:

• Dune-1 Dune - Frank Herbert
• Foundation-3 Second Foundation - Isaac Asimov
• The Martian - Andy Weir (no series)

This naming convention helps organize books on reMarkable and makes series sort correctly.

EPUB Conversion

When sending EPUB files, the plugin converts them to PDF optimized for reMarkable:

• Page size: Matched to your device (reMarkable 2, Paper Pro, or Paper Pro Move)
• Typography: Configurable font family, size, and line height
• Margins: Configurable for comfortable reading
• Full-bleed cover: The cover image is extracted and added as the first page without margins, scaled to fit the page width and top-aligned. Any padding at the bottom uses the dominant color from the cover's edge for a seamless appearance.

A converted EPUB displayed on a reMarkable Paper Pro Move.

How It Works

The plugin creates document files directly in the reMarkable desktop app's local storage:

Platform	Path
macOS	~/Library/Containers/com.remarkable.desktop/Data/Library/Application Support/remarkable/desktop/
Windows	%LOCALAPPDATA%/remarkable/desktop/
Linux	~/.local/share/remarkable/desktop/

For each book, it creates:

• {uuid}.pdf - The book content
• {uuid}.metadata - Document metadata (title, parent folder, timestamps)
• {uuid}.content - Page structure and formatting info
• {uuid}.local - Local sync metadata
• {uuid}.pagedata - Page tracking data
• {uuid}/ - Directory for annotations
• {uuid}.thumbnails/ - Thumbnail images

After sending books, restart the reMarkable desktop app to trigger sync to the tablet.

Packaging for Distribution

Create a distributable ZIP file:

make dist
# Creates remarkable_sync-X.Y.Z.zip

Users can install via Preferences → Plugins → Load plugin from file.

Acknowledgments

The sync approach — using the reMarkable desktop app as a bridge, which only requires a free reMarkable Connect account (no paid subscription) — was inspired by the Remarcal team's work.

License

GPL v3