Calibre – Comprehensive E-book Library Management

What is Calibre?

Calibre is a powerful, free, and open-source e-book management application that has become the definitive solution for organizing digital book collections. Created by Kovid Goyal in 2006, Calibre provides comprehensive tools for managing, converting, editing, and reading e-books across virtually every format and device.

More than just a library organizer, Calibre functions as a complete e-book ecosystem. Its format conversion engine supports dozens of input and output formats, enabling books to work on any e-reader. The built-in e-book viewer renders content beautifully, while the editor allows modifying EPUB and AZW3 files directly. A content server shares your library across your network or the internet.

Calibre’s metadata management capabilities automatically fetch book information, covers, and descriptions from online sources. Custom columns enable organizing books by any criteria you choose. Whether managing a handful of books or libraries with tens of thousands of titles, Calibre scales to meet your needs.

Key Features and Capabilities

Library Management

Organize books with automatic metadata retrieval from Amazon, Google Books, and other sources. Sort by author, series, tags, ratings, or custom fields. Multiple library support enables separate collections for different purposes.

Format Conversion

Convert between virtually any e-book format: EPUB, MOBI, AZW3, PDF, DOCX, HTML, TXT, and many more. Fine-grained control over conversion parameters, page breaks, fonts, and layout produces professional results.

Device Synchronization

Connect Kindle, Kobo, Nook, and other e-readers directly to sync books. Automatic conversion ensures books display correctly on each device. Wireless device connections available for supported readers.

Content Server

Built-in web server shares your library over the network. Access books from any device with a browser. OPDS catalog support enables compatible reading apps to browse and download directly.

E-book Viewer

Read books directly in Calibre with customizable fonts, colors, and margins. Bookmarks, highlighting, and notes supported. Dictionary lookup and text-to-speech integration available.

E-book Editor

Edit EPUB and AZW3 files with the built-in editor. Modify CSS, fix formatting issues, update metadata, and restructure table of contents. Live preview shows changes immediately.

System Requirements

Desktop Requirements

Calibre runs on Windows 10+, macOS 10.14+, and Linux. Requires approximately 175 MB disk space for installation plus storage for your library. Memory usage scales with library size—4 GB RAM recommended for large collections.

Installation Guide

Installing on Windows

# Download from calibre-ebook.com
# Run installer

# Using Chocolatey
choco install calibre

# Using Winget
winget install calibre.calibre

# Portable version available
# Extract and run from any folder

Installing on macOS

# Download DMG from calibre-ebook.com
# Drag to Applications

# Using Homebrew
brew install --cask calibre

Installing on Linux

# Official binary installer (recommended)
sudo -v && wget -nv -O- https://download.calibre-ebook.com/linux-installer.sh | sudo sh /dev/stdin

# Flatpak
flatpak install flathub com.calibre_ebook.calibre

# Ubuntu/Debian (may be older version)
sudo apt install calibre

# Arch Linux
sudo pacman -S calibre

Basic Operations

Adding Books

Methods:
1. Drag and drop files onto window
2. Click "Add books" button
3. Use Ctrl/Cmd + A shortcut
4. Add from ISBN or URL

Supported Formats:
- EPUB, MOBI, AZW/AZW3
- PDF, DJVU
- FB2, LIT, PRC
- HTML, DOCX, RTF
- TXT, ODT
- CBZ, CBR (comics)

Adding Options:
- Add as new book
- Add to existing book (formats)
- From folder recursively

Managing Metadata

Edit Metadata (Ctrl/Cmd + E):
- Title, Author, Series
- Tags, Publisher, Date
- Rating, Comments
- Cover image
- Custom columns

Download Metadata:
1. Select book(s)
2. Right-click > Download metadata
3. Choose source (Amazon, Google, etc.)
4. Review and apply changes

Bulk Metadata Edit:
1. Select multiple books
2. Right-click > Edit metadata
3. Modify common fields
4. Apply to all

Format Conversion

Basic Conversion

Convert Book:
1. Select book
2. Click "Convert books" or press C
3. Choose output format
4. Adjust settings if needed
5. Click OK to convert

Common Conversions:
- EPUB ? MOBI (Kindle)
- PDF ? EPUB
- DOCX ? EPUB
- AZW3 ? EPUB
- EPUB ? AZW3 (Kindle)

Conversion Settings

Page Setup:
- Output profile (device-specific)
- Input profile
- Margins
- Page size (for PDF output)

Look & Feel:
- Font families
- Font sizes
- Line height
- Text justification
- Embed fonts

Structure Detection:
- Chapter detection
- Remove headers/footers
- Insert page breaks

Table of Contents:
- Generation method
- Heading levels
- Custom XPath expressions

EPUB Output:
- Flatten CSS
- Split at chapters
- Insert inline TOC

MOBI/AZW3 Output:
- Personal Doc tag
- Compression
- File type (KF8, Both)

Device Integration

Connecting E-readers

Supported Devices:
- Amazon Kindle (all models)
- Kobo (all models)
- Barnes & Noble Nook
- PocketBook
- Onyx Boox
- Generic USB e-readers
- Android/iOS devices (via app)

Connecting:
1. Plug in device via USB
2. Calibre auto-detects
3. Device appears in toolbar

Sending Books:
1. Select book(s)
2. Click "Send to device"
3. Choose location (main/card)
4. Conversion happens automatically if needed

Wireless Connection

Kobo Wireless:
1. Enable in Kobo settings
2. Calibre detects over WiFi
3. Sync wirelessly

Content Server (Any Device):
1. Start content server
2. Access from device browser
3. Download books directly

Content Server

Starting the Server

GUI:
Connect/share > Start content server

Command Line:
calibre-server --port 8080 /path/to/library

Options:
--port PORT          # Listen port (default 8080)
--username USER      # Basic auth username
--password PASS      # Basic auth password
--url-prefix PREFIX  # URL prefix for reverse proxy

Access:
http://localhost:8080
http://server-ip:8080

OPDS Catalog

OPDS URL:
http://server-ip:8080/opds

Compatible Apps:
- Moon+ Reader
- Aldiko
- FBReader
- KyBook
- Marvin (iOS)
- Many more

Features:
- Browse by author, series, tag
- Search library
- Download any format

Plugins

Popular Plugins

DRM Removal:
- DeDRM (requires separate install)
- Removes Kindle/Adobe DRM

Metadata Sources:
- Goodreads
- LibraryThing
- Google Books

Device Support:
- KOReader Sync
- Kindle Collections
- Kobo Utilities

Other:
- Count Pages
- Embed Comicbook Metadata
- Generate Cover
- Quality Check

Installing Plugins:
Preferences > Plugins > Get new plugins

Command Line Interface

calibredb Commands

# Add book to library
calibredb add /path/to/book.epub

# Add with metadata
calibredb add book.epub --title "Title" --authors "Author"

# List books
calibredb list

# Search library
calibredb list --search "author:Tolkien"

# Export books
calibredb export --all --single-dir /path/to/export

# Remove book
calibredb remove 123

# Show metadata
calibredb show_metadata 123

# Set metadata
calibredb set_metadata 123 --field tags:"fiction,fantasy"

# Library info
calibredb list --fields title,authors,formats

ebook-convert Commands

# Basic conversion
ebook-convert input.epub output.mobi

# With options
ebook-convert input.epub output.mobi \
  --output-profile kindle_pw3 \
  --pretty-print

# From URL
ebook-convert http://example.com/page.html output.epub

# List all options
ebook-convert --help

# Format-specific help
ebook-convert input.epub output.mobi --help

Advanced Features

Custom Columns

Preferences > Add your own columns

Column Types:
- Text (single/multiple values)
- Integers, Floats
- Dates
- Yes/No
- Rating
- Series
- Enumeration

Examples:
- Read Status (Yes/No)
- Source (Enumeration)
- Date Read (Date)
- My Notes (Long text)

Search Syntax

# Basic search
title:hobbit
author:tolkien
tags:fantasy

# Operators
author:tolkien AND tags:fantasy
author:tolkien OR author:lewis
NOT tags:read

# Comparison
rating:>=4
date:>2020-01-01
#pages:>300

# Regular expressions
title:"~lord.*rings"

# Custom columns
#status:read
#source:kindle

Keyboard Shortcuts

General

Ctrl/Cmd + N    - New empty book
Ctrl/Cmd + A    - Add books
Ctrl/Cmd + E    - Edit metadata
Ctrl/Cmd + D    - Download metadata
C               - Convert selected
S               - Send to device
V               - View book
Del             - Remove book
Ctrl/Cmd + R    - Remove formats
F               - Toggle search focus

Best Practices

Library Organization

Tips:
1. Let Calibre manage file locations
2. Use tags consistently
3. Set up series properly
4. Download metadata for all books
5. Use custom columns for tracking
6. Regular library maintenance
7. Backup library folder

Naming Convention:
Author/Title (Series #)/Book.format
Managed automatically by Calibre

Conclusion

Calibre provides everything needed to manage an e-book collection of any size. Its powerful conversion engine, comprehensive metadata management, and device synchronization capabilities make it indispensable for e-book enthusiasts.

Whether organizing a personal library, converting formats for different devices, or sharing books across your network, Calibre delivers professional results with open-source accessibility.