About calibre

 
calibre is a free and open source e-book library management application developed by users of e-books for users of e-books. It has a cornucopia of features divided into the following main categories:
  • Library Management

    calibre manages your e-book collection for you. It is designed around the concept of the logical book, i.e., a single entry in your library that may correspond to actual e-book files in several formats.

    calibre can sort the books in your library by: Title, Author, Date added, Date published, Size, Rating, Series, etc.

    In addition, it supports extra searchable metadata:

    • Tags: A flexible system for categorizing your collection however you like
    • Comments: A long form entry that you can use for book description, notes, reviews, etc.

    You can easily search your book collection for a particular book. calibre supports searching any and all of the fields mentioned above. You can construct advanced search queries by clicking the helpful "Advanced search" button to the left of the search bar.

    You can export arbitrary subsets of your collection to your hard disk arranged in a fully customizable folder structure.

    Finally, calibre will even go out onto the internet to find book metadata based on existing title/author or ISBN information. It can download various types of metadata and covers for your books, automatically. The metadata system is written using plugins so that different types of metadata sources can be supported in the future.

  • E-book conversion

    calibre can convert from a huge number of formats to a huge number of formats. It supports all the major e-book formats. The full list of formats can be found here.

    The conversion engine has lots of powerful features. It can rescale all font sizes, ensuring the output e-book is readable no matter what font sizes the input document uses. It can automatically detect/create book structure, like chapters and Table of Contents. It can insert the book metadata into a "Book Jacket" at the start of the book.

  • Syncing to e-book reader devices

    calibre has a modular device driver design that makes adding support for different e-reader devices easy. At the moment, it has support for a large number of devices. Syncing supports updating metadata on the device from metadata in the library and creation of collections on the device based on the tags defined in the library. If a book has more than one format available, calibre automatically chooses the best format when uploading to the device. If none of the formats is suitable, calibre will automatically convert the e-book to a format suitable for the device before sending it.

  • Downloading news from the web and converting it into e-book form

    calibre can automatically fetch news from websites or RSS feeds, format the news into a ebook and upload to a connected device. The ebooks include the full versions of the articles, not just the summaries. Examples of supported news sites include:

    • The New York Times
    • The Wall Street Journal
    • The Economist
    • Time
    • Newsweek
    • The Guardian
    • ESPN
    • and many, many more…

    calibre has over three hundred news sources and the news system is plugin based, allowing users to easily create and contribute new sources to calibre. As a result the collection of news sources keeps on growing!

    If you are interested in adding support for a news site, read the User Manual. Once you have successfully created a new recipe, you can share it with other users by posting it in the calibre forum or sending it to the calibre developers for inclusion in calibre.

  • Comprehensive e-book viewer

    calibre has a built-in ebook viewer that can display all the major ebook formats. It has full support for Table of Contents, bookmarks, CSS, a reference mode, printing, searching, copying, customizing the rendering via a user style sheet, embedded fonts, etc.

  • Content server for online access to your book collection

    calibre has a built-in web server that allows you to access your ebook collection using a simple browser from any computer anywhere in the world. It can also email your books and downloaded news to you automatically. It has support for mobile devices, so you can browse your collection and download books from your smartphone, Kindle, etc.

  • E-book editor for the major e-book formats

    calibre has a built-in editor that allows you to edit e-books in the most popular e-book formats, EPUB and AZW3 (Kindle). The editor has a live preview showing the effect of your changes as you make them and includes a comprehensive checking tool that can find many of the most common errors in book structure and formatting and even fix some of them automatically. The editor also has an integrated review tool to visually inspect the differences between different versions of the book. For more about the editor, see here.

calibre started life on 31 October, 2006, soon after the release of the SONY PRS-500, the first e-ink based reader to be sold commercially in the US. At the time, I was a graduate student, with a lot of time on my hands. The PRS-500 did not work at all with Linux, my operating system of choice, so I decided to reverse engineer the USB protocol that it used, to get it working on Linux. This was accomplished with the help of the fine folks over at mobileread.com and calibre was born, albeit named libprs500.

At the time there were no satisfactory tools to convert content into the LRF format, used by the SONY reader, so I decided to implement a converter to convert the most popular e-book formats to LRF. This converter proved to be wildly popular and far better than the (mostly non-existent) offerings from SONY. It was picked up and used by various publishing houses and content digitizers to produce the first generation of books in the LRF format.

As my e-book collection grew, I realized that managing it was quickly becoming unwieldy, so I decided to write a graphical interface to libprs500 to make it easier. This became calibre, in its present form, as a comprehensive e-book management tool. libprs500 was renamed to calibre in mid-2008. The name calibre was chosen by my wife, Krittika. The libre in calibre stands for freedom, indicating that calibre is a free and open source product, modifiable by all. Nonetheless, calibre should be pronounced as cali-ber, not ca-libre.

The news downloading feature, one of calibre's most popular, has an interesting story behind it. I used to subscribe to Newsweek, back when it was still a real news magazine. But one fine day, Newsweek simply stopped being delivered to my house and no matter how much time I spent on the phone with various sales reps, it simply would not start again. Since I'd just got my first e-book reader at the time, I decided to add the ability to download and convert websites to calibre. From the beginning, I decided to make it as modular as possible, so that other people could contribute "recipes" for different news sites. The calibre cookbook has kept on growing and now calibre has recipes for over three hundred news sources in many different languages.

Today calibre is a vibrant open-source community with half a dozen developers and many, many testers and bug reporters. It is used in over 200 countries and has been translated into a dozen different languages by volunteers. calibre has become a comprehensive tool for the management of digital texts, allowing you to do whatever you could possibly imagine with your e-book library. Reading is very important to me and one of my goals has always been to prevent either the fragmentation or the monopolization of the e-book market by entities that care solely for short-term goals. As the calibre community continues to grow, driven by book lovers, for book lovers, hopefully it will always present an alternative for people that love to read e-books and want to be in control of their own digital libraries.

Kovid Goyal
November 2009

Asking for help

The best places to ask for help with calibre are the very active calibre forum at mobileread.com, where there are a number of friendly and knowledgeable long time users/developers of calibre. In addition, there is the calibre Facebook fan page and #calibreforum on Twitter.

Reporting issues and asking for new features

If you discover a problem with calibre or would like to request a new feature, the best place to do it is via the calibre Bug tracker. Be aware that calibre is developed by volunteers, which means that your bug report/feature request may or may not get attention, so if you are looking for help, the best place is the forum linked to above.

calibre is an open source application that uses a large number of other open source libraries and is developed on Linux, an open source platform, and as such, it has benefited from the work of large numbers of people, some of whom are listed below. I've tried to be as exhaustive as possible, but, if I have omitted your contribution, please let me know.

Contributors of code/bug fixes

In no particular order:

  • Marshall Vandegrift: For epub2lrf, lit2oeb, oeb2mobi and various improvements in the html2lrf code, as well as the basic framework for the conversion pipeline in the 0.6.x series
  • John Schember: For the new calibre device driver framework, various GUI enhancements and several input and output format plugins and the "Get Books" feature
  • Charles Haley: For custom columns, saved searches, restrictions, the wireless device driver, lots of other help/ideas
  • Gregory Riker: For MOBI indexing, catalogs, the iPad driver
  • Roger Critchlow: For the initial implementation of lrs2lrf
  • Anatoly Shipitsin: For fb2lrf and fb2-meta
  • Ori Avtalion and WayneD for various bug fixes
  • Tijmen Ruizendaal for the Be Book driver
  • Igor Skochinsky (for various bits of reverse engineering without which calibre would never have gotten off the ground)
  • Darko Miletic: For a large number of news recipes
  • Grant Drake: For various plugins including Open with, search the internet and goodreads integration
  • Timothy Legge and David Forrester: For Kobo support in calibre

Graphics and design

  • Nicholas Holland and the guys at Centresource for the website design
  • diaboNL for the reader icon
  • Caleb Avery and Kamil Tatara for the calibre logo
  • subtlepatterns.com for various textures
  • The Oxygen project and Kamil Tatara for various icons

Recipe writers

Too many people have contributed recipes to list here, but their contributions are a big part of calibre.

Translators

The list of translators is available here

Other projects whose code/libraries calibre uses/links against

  • Python
  • Qt
  • PyQt
  • rtf2xml
  • poppler
  • feedparser
  • pylrs
  • BeautifulSoup
  • mechanize
  • pictureflow
  • lxml
  • cssselect
  • Hyphenator
  • sqlite
  • chardet
  • podofo
  • imagemagick
  • libmtp
  • Python Imaging Library
  • Sphinx
  • django
  • odfpy
  • cssutils
  • git
  • ICU
  • CherryPy
  • python routes
  • dateutil
  • dnspython
  • pywin32
  • python-dbus
  • QtCurve

The Launchpad, Google Code and Sourceforge.net services for providing file and code hosting for calibre releases.

Last, but not least I'd like to thank the folks at mobileread.com for creating a wonderful community for us e-book lovers to gather round.

  • You can see usage statistics for calibre here.
  • You can see usage statistics for the various news sources in calibre here.