NetRead Software & Services
NetRead Software and Services

ONIX Explained

ONIX stands for Online Information eXchange. It refers to a standard format that publishers can use to distribute electronic information about their books to wholesale and retail booksellers, other publishers, and anyone else involved in the sale of books.


It's a proven fact that the more information customers have about a book, the more likely they are to buy it. In the brick and mortar world, the jacket cover of a book contains much of the promotional information about that book: cover design, synopsis, reviews, author biography, etc. All of this information (also known as book metadata) draws the potential reader into a book and helps to sell it.

The Internet has grown as a popular place to buy books. Online, however, there is no physical book to pick up and peruse. Replacing that experience is a web page devoted to the book that can be designed to carry all the rich information of the jacket cover, and more, such as audio and video files pertaining to the book. And again, the richer the data, the better the chances are for selling the book.

However, getting that data about each book from publishers to booksellers has been a challenge, complicated by the fact that prior to 2001 each major industry database company (such as Ingram, Bowker, and Amazon) had had a different format preference for receiving the data. This lack of a standard made it difficult and time-consuming for publishers to format and exchange their book information.

Enter the ONIX initiative. ONIX was developed as a solution to two modern problems: (1) the need for richer book data online; and (2) the widely varying format requirements of the major book wholesalers and retailers. Throughout 1999, the American Association of Publishers (AAP) worked together with the major wholesalers, online retailers, and book information services to create a universal, international format by which all publishers, regardless of their size, could exchange information about books. The group unveiled ONIX 1.0 in January 2000. Since then, improvements to the original version have produced ONIX International, which refers to the most updated ONIX standard.

Much of ONIX is based on the pre-existing EPICS (EDItEUR Product Information Communication Standards), a much broader standard for defining products which was developed internationally by EDItEUR, drawing on the combined experience of Book Industry Study Group (BISG) in the US and Book Industry Communication (BIC) in the UK.

How ONIX Works

The ONIX standard defines both a list of data fields about a book and how to send that data in an "ONIX message." ONIX specifies over 200 data elements, each of which has a standard definition, so that everyone can be sure they're referring to the same thing. Some of these data elements, such as ISBN, author name, and title, are required; others, such as book reviews and cover image, remain optional. While most data elements consist of text (e.g., contributor biography), many are multimedia files, such as images and audio files. (It is particularly these optional fields--excerpts, reviews, cover images, author photos, etc.--that lead to more sales online.)

An ONIX message is a set of data elements defined by "tags" that is written in the computer language XML (eXtensible Markup Language) and that conforms to a specific template, or set of rules, also known as the ONIX DTD (Document Type Definition). The DTD defines, among other things, how to order the data elements, and how the elements are interrelated.

ONIX uses XML for a number of reasons:

  1. XML is optimized for creating complex documents and transmitting and exchanging data between computers.
  2. XML is text-readable, meaning that humans as well as computers can recognize and read the data. Most tags, which define each book data element, consist of English words or abbreviations--for instance, an ONIX message would list the Publisher's name as follows: "<PublisherName>Scribner's</PublisherName>". These factors make it easier for smaller organizations to design and implement ONIX-compliant systems.
  3. XML software is inexpensive, meaning that even smaller publishers can use it, which was a major goal of the ONIX committee.

Creating an ONIX message involves two steps: (1) organizing the book data into ONIX-specified fields and storing it in a database; and (2) using an XML software application and the ONIX DTD (the set of rules) to organize and tag that data. A single ONIX message may contain data about multiple books.

An ONIX message is transmitted across networks and the Internet the same way other data is--for instance, as an email attachment or by ftp.

Once an ONIX message is received by, say, an online retailer, the same tools (an XML software application and the ONIX DTD) are used to verify the data's integrity. From that point, the retailer translates that data into what you see on a web page. (The matter of how much of the data is displayed on their web page is strictly up to the retailer.)

The Future of ONIX

The book publishing world is now moving towards ONIX. Major online booksellers, such as Amazon,, Borders, and Powell's, are working to make ONIX the sole standard for transmitting information about books. Major wholesalers and catalog publishers, such as Ingram, Baker & Taylor, and R.R. Bowker, have also adopted the ONIX standard. Wider industry acceptance will lead to increased efficiencies in the transfer of book data, which will ultimately benefit book sales.

Future issues to be addressed include adding standards for electronic books and incorporating concepts of digital rights. In addition, processes for certifying that transmitted data is valid and correct are being developed. ONIX will continue to evolve as needs are identified.

ONIX is now published and maintained by EDItEUR in association with the Book Industry Study Group (BISG) in the U.S. and BIC in the U.K. The latest version of ONIX is referred to as ONIX International.

How Do Publishers Become ONIX Compliant?

The ONIX International guidelines can be found at the official ONIX web site, which lists the defined data elements and corresponding tags. Publishers can choose to either manually convert their catalogs to become ONIX compliant or use a service such as NetRead's JacketCaster to do the conversion. (JacketCaster makes it easy for publishers to maintain complete, current ONIX-compliant book information with all wholesalers and online retailers, as well as in their own web and print catalogs. For more information, click here or send email to

Links The official ONIX web site. The Association of American Publishers (AAP). The AAP is the principle trade association of the United States book publishing industry. EDItEUR is an international not-for-profit organization, based in London, that coordinates the development, promotion, and implementation of EDI (Electronic Data Interchange) and other e-commerce standards in the book and serials sectors. EDItEUR publishes and maintains ONIX. Book Industry Communication (BIC) is a U.K. membership-based not-for-profit association, sponsored by The Publishers Association, The Booksellers Association, The Library Association, and The British Library to develop and promote standards for electronic commerce and communication in the book and serials industry. It promotes and supports ONIX in the U.K. and provides U.K. input into the development of ONIX. The Book Industry Study Group, Inc. (BISG) promotes and supports ONIX for the U.S. publishing industry and provides U.S. input into the development of ONIX. As a membership-supported, not-for-profit research organization comprised of several sectors from the publishing community, its goal is to provide accurate and current research information about the industry for its members and others.

© 2024 NetRead Software and Services, LLC. All rights reserved.