ONIX for Books (usually just called ONIX) is an international standard enabling publishers to exchange information about all types and formats of books..

The ONIX specification is developed and maintained by EDItEUR, a UK-based not-for profit trade standards body with over 110 members in 25 countries. ONIX development is guided by an International Steering Committee that includes diverse representation from its member countries.  Both the Canadian English (BookNet Canada) and French (BTLF) language markets are represented.

What is ONIX?

ONIX is a standard format or "language" that publishers need to use when distributing electronic information about books to wholesale, e-tail and retail booksellers, other publishers, and any other supply chain partner involved in the production, review or sale of books.

ONIX is not a database and you don't have to change your database in order to use it. It isn't a programming language and it can't "do" anything. It exists to describe books and provides two things: Code Lists with their standard international definitions that support clear communication, and a file format for the delivery of book information.

ONIX Codes can be used to clarify information sent via Excel spreadsheet, delimited ASCII (tab or comma, with our without headings), fixed width, HTML, Word, InDesign, email message or hard copy, but the ONIX file format is the preferred method. It's in XML and as a structured system it can support a comprehensive book record with tools for validation and standardized text that give ONIX a distinct advantages over other formats.

The ONIX standard defines both a list of data fields about a publication and how to send that data in an ONIX message. ONIX specifies and defines the data elements so that everyone can be sure they're referring to the same thing. Publishers can use as many or as few of the data elements they wish to record and transmit. These are not just limited to facts and figures and textual description: multimedia files, such as images and audio files are becoming increasingly important as ways of encouraging sales and enriching the record.

The ONIX message is a set of data elements defined by tags written in XML (eXtensible Markup Language).  The XML definitions provided its schema defines, among other things, how to order the data elements and how the elements are interrelated.

Current North American Metadata is Defined by:

EDItEUR’s complete ONIX documentation:

ONIX Code List 66:

Subject classifications:


ONIX 2.1 is No Longer a Supported Standard

Codelist Issue 36 (released January 2017) is the final code list for ONIX version 2.1 and the only one required going forward. Not being supported does not mean it is not used. ONIX 2.1 can remain in use for however long two companies choose to continue to trade data using that version. In North America, ONIX 2.1 continues to be used for many physical book metadata transfers, though this is an ever-changing landscape.

Amazon's 3.0 Request

Amazon has requested that all physical book ONIX feeds be submitted in ONIX 3.0 by December 31, 2020. No deadline has been specified for digital ONIX but it is already dominated by ONIX 3.0 and the expectation is that it will follow shortly thereafter. This request applies globally to all Amazon divisions. Watch for more announcements from other retailers and companies supplying data.

BookNet Canada has compiled supporting documentation at https://booknetcanada.atlassian.net/wiki/spaces/UserDocs/pages/1149894942  as well as a benchmarking / progress calendar for data providers at https://booknetcanada.atlassian.net/wiki/spaces/UserDocs/pages/1144129720.

BookNet Canada continues to recommend:

  • All data suppliers continue to support ONIX 2.1 for North American data transfer

  • If you can support ONIX 3.0 in addition to ONIX 2.1 please do so and ensure trading partners are aware of the option. This will facilitate retailers and other aggregators developing ONIX 3.0 support

  • No one should switch from ONIX 2.1 to ONIX 3.0 without first notifying their trading partners.  We think you'll find that you will still need to support ONIX 2.1

  • New implementations of ONIX have a hard decision:  ONIX 2.1 will not be supported for much longer but it remains the practical choice in our market.

Information for data suppliers to BiblioShare is here.

ONIX makes it easier to sell books

Look at a bestseller at any online retailer. Compare that record to the same book at another online retailer's. You'll find some differences in presentation, one might display more than another but the information will usually match. That information was provided as an ONIX record.  Collectively this information is known as the book's metadata. It plays a large role in online book sales (titles with metadata outsell those without, eight to one) so it is in the best interest of both bookstores and publishers to include metadata for as many titles as possible.  

All books displayed on-line should be supported by cover art, title, author(s), description and author bio(s). It would be better still if if consumers could see reviews, endorsements, prizes the book or author have won. Better again if it provided citations to, and rankings from, best seller lists as well as a listing of events the author will be speaking at.  Behind the display, metadata supports systems providing search indexing as well as who can supply retailers the book, in which territories and at what price.  Retailers and libraries even want to be able to promote their local authors and metadata can include the city where the author lives.  Metadata goes two ways:  When a booking happens, publicists are told, who can add it to the ONIX record to help promote the store and the author.

Book selling and publisher marketing needs evolve continuously. ONIX is a standard that grows with those needs. Audiobooks, ebooks, or print – anything with an ISBN is supported as well as many other products typically sold through, or used by, bookstores.

Tracking and maintaining all that possible information is complex but a basic ONIX record is not.  It is a standardized format designed to be updated and sent regularly to confirm the book's currency and availability.  The record can grow and be updated as you and your trading partners' needs grow.  ONIX as one file that can serve many partners allows you to maximize the benefit of adding support.


Send your questions and comments to biblio@booknetcanada.ca.

BookNet Canada’s ONIX services




BookNet's E-news also carries announcements of major changes to ONIX. Subscribe here.

ONIX for Book Implementation LISTSERV

Implementation questions are routinely discussed on the ONIX_Implement mailing list, and notices of ONIX developments are sent out to the list as well as to national groups. Anyone developing or interested in using ONIX can join:

The message archive goes back beyond 2000 and covers a wide range of topics. Correct ONIX usage may be a matter of correctly matching code list definitions but it often depends on a consensus between suppliers and end users. This can vary between markets (each country has its own flavour of ONIX) and this forum is where the consensus begins.

Collected resources on the transition from ONIX 2.1 to 3.0: