Why Your Book Needs An ISBN

Actually, you do not need an ISBN to sell your book on your own web site or in person.

But to sell your book to bookstores and libraries, not only does your print book or digital book (i.e., audiobook, ebook, or PDF book) need an ISBN, it needs a unique ISBN! Are you one of the authors complaining about the need to buy multiple ISBNs for your book title? Read on…

First, what is an ISBN?

An ISBN (International Standard Book Number) is a book title identifier. ISBNs made use of the Standard Book Numbering (SBN) code created by Gordon Foster, an Irish statistician, for booksellers in 1966.  An ISBN (pronounced eye-s-bee-n) identifies a particular title, edition, and format of a book, as well as the registrant that registers that International Standard Book Number for use.

An ISBN is a series of either ten or thirteen numbers that can be broken down into subgroups with a hyphen between them. A ten digit number indicates that the book was published prior to January 1, 1997. Thirteen digit numbers indicate the book came out in 1997 or later. For example, here are ISBNs for two of my client’s books: ten digit 0-9746701-0-3, and thirteen digit 978-0-9829690-0-7

To see an ISBN on a book, look on the verso, (i.e., the back) of the title page of a book. Remember that ISBNs only consist of ten or thirteen numbers with only hyphens for separation of the subgoups of numbers within the ISBN. Don’t confuse an ISBN with a library call number for a book. You can distinguish the two because there there are no letters or periods in an ISBN, only hypens. Book publishers often include library call numbers as well as ISBNs on the verso of their author’s title pages.

ISBNs are not barcodes

Note that an ISBN is not identical to a barcode either. Barcodes were first used in a supermarket in Troy, Ohio thirty-seven years ago. The first customer for a bar-coded item, Clyde Dawson, bought a pack of Wrigley’s juicy fruit chewing gum from the store cashier, Sharon Buchanan.

The idea of creating a barcode came from the dots and dashes in Morse code (used by Telegraph companies like Western Union for sending messages by wire). In 1952 Norman Woodland and Bernard Silver patented their barcode idea. Later, after the advent of scanners, a Harvard Business School MBA, Alan Haberman, popularized use of barcodes by supermarkets. He formed a committee and they called their system of bar coding the Universal Product Code (UPC).

UPC barcodes increased the speed with with retail store items were purchased. UPCs also improved store revenues by cutting down on shoplifting. Billions of dollars were saved. And now there are around five billion bar codes scanned every day in retail shops around the globe.

The similarity between barcodes and ISBNs

Bar codes are identifiers of a class of items. For example, all Wrigley’s juicy fruit gum packages use the same barcode number. That way, the store’s scanners at the checkout counter charge a uniform amount for each package of a particular product it sells.

Bookstores used ISBNs as their own special kind of barcode, rather than UPCs. That’s because an ISBN identifies not just a class of items, i.e., a book, but a specific instance of that class that we call a “title”. The ISBN indicates the title and other characteristics of a particular book. All copies of the same book title are identified by their common ISBN. That makes ISBNs quite useful to bookstores for inventory control and for selling books. Bookstores now make use of a special barcode with either 15-digits or 18-digits that include a 10-digit or 13-digit ISBN.

You’ll see this barcode printed on the back cover of books in bookstores. It will feature two blocks of vertical black stripes with numbers above them. Barcodes created for bookstores use an additional block of five numbers after the ISBN to show a suggested retail price for the book and the currency that price is in. These barcodes can be scanned at the checkout counter when someone buys that title.

With the expansion of ISBNs from 10-digit numbers to 13-digit numbers, the ISBN came to include a standardized EAN-13 barcode as a three-digit prefix to the old ten-digit ISBN.

The EAN-13 barcode is a more general product identification number than either the ISBN or the 12-digit UPC  that you’ve seen used by supermarket scanners in the United States. EAN is short for European Article Number, but its current name is “International Article Number”. EAN-13 is a global standard for barcodes used by retailers. Global standardization of barcodes is why the first three digits of any book’s 13-digit ISBN will be 978 or 979. Those numbers mean the product for sale is a “book”.

The differences between barcodes and ISBN numbers

What about the rest of the 13-digit ISBN number – the ten digits that follow the EIN-13 barcode? What do they stand for?

The book industry, and bookstores in particular, use these ten digits, the ISBN, to identify a subclass of books called a title. Unlike a barcode that simply identifies a book as a book, an ISBN identifies characteristics of individual books. As a result, the ISBN can be used to track sales of a specific book by its title and by other specific characteristics belonging to that title. For example, bookstore statistics include not only the total number of sales of titles each year, they also can include the number of hardbound books sold as opposed to paperbacks sold each year.

The additional information contained within an ISBN includes the language of your book, the format of your book, and your publisher or other registrant of your ISBN. The last digit of an ISBN is a check digit, used for quality control.

Note that libraries use a different jargon than digital book publishers use to describe the kind of information indicated by a title’s ISBN. Librarians call this kind of information, i.e., book title, format, publisher, etc. bibliographic information, meaning it pertains to books. Digital publishers call it metadata, meaning that it is a top level of data that describes the book. Either way, as we’ll see in part 2 of this series, this information is very important when it comes to selling your book to libraries as well as bookstores.

Why do you need to pay for multiple ISBNs?

The bibliographic information, or metadata, embedded into your ISBN is the reason why each time you use a new format for your book or you publish your book in a new language, as a new edition, or with a different publisher, you must use a new ISBN number. Even if the text in a new version of a book is exactly the same as the original, you must buy a new ISBN if the format is different, e.g., it is hardcover, softcover, an ebook or an audiobook.

Most authors intend to create more than one format for their book. Perhaps too, you will want to revise your book and create a new edition. Or maybe you will write more books. If you are a self-publisher or if your publisher does not provide you with an ISBN, it may be beneficial to you to buy a block of 10 ISBNs all at once from the official “Agency” that provides ISBNs in your country.

In the United States the RR Bowker Company is that official ISBN Agency. Bowker is one of the biggest sources of statistics for the American publishing industry and libraries. On Bowker’s web site you can read their official FAQs about ISBNs. Other countries too each have their own official Agencies that issue ISBNs.

How do you buy an ISBN?

Bowker sells packages of ten or more ISBNs at deeply discounted prices. Bowker recommends buying enough ISBNs to meet your needs for the next five years. Publishers and POD (Print-on-Demand) companies usually buy ISBN”s in greater bulk and hand them out to authors for free or a small fee. If you think you might sell your book in stores, Bowker also sells EAN-13 barcodes for books that can be scanned by stores.

If you are paying an author services or a POD company to put together and print your book , check out this article about a UK author’s experience by Carla King, “The Pitfalls of Using Self-Publishing Book Packages,” particularly the cautionary tale in the section, “Beware the ISBN Acquisition.” This article can be found online at PBS.org,  Readbility. com, and other sites.

Self-publishers who prefer to buy only a single ISBN can find authorized resellers online who charge between $60 and $120 for a single ISBN. Your ISBN will identify you, the registrant of that ISBN, as an either an “independent publisher” (a not-particularly-useful label when selling to libraries!), or for an additional fee, your ISBN will identify you, the registrant, by a unique business name you choose for publishing and marketing your book. Tip: If you wish to make it easy for your customers to remember, your business name for your book can be the same name you use for you book’s web or blog site.

When do you buy an ISBN?

If possible, buy an ISBN before you finish your book! That’s because, hopefully, you’ll be out there marketing your book even before it’s done. Your ISBN should be included in your book itself and on any press release or the “one-sheet” that gets sent along with a review copy of your book prior to publication. Your ISBN should in go into the section on how-to-order your book that’s included in any marketing material that you post online or mail out both prior to and after you publish your exciting new book!

Although you can buy an ISBN after your book is published, think long and hard about whether you want to market your book to bookstores and/or to libraries. Bookstores require a barcode, usually one containing an ISBN for inventory control and checkout, and in the next post in this series, you’ll learn why an ISBN is vital if you want to get more than a handful of library sales!

Next:  “How Librarians Use ISBNs and Barcodes

My new book, Marketing Your Book to Libraries: An Insider’s Guide for Authors by Nancy K. Humphreys is on sale now at a 20% discount! Click here. Or check out my 2-book sale that includes Class Act: Sell More Books Through School and Library Author Appearances by Barbara Techel, available at WordmapsIndexing.

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  1. Plaxides says:

    I am a new writter, do I need both the isbn and barcode for my book?

    • Nancy says:

      You need an isbn for a print book. You (or your publisher) can purchase a barcode that goes on the back cover also from R.R. Bowker Company. Ebooks, audiobooks and downloadable PDF books do not need a barcode (unless they are on a disk with a cover). Nancy

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