What is an ISBN and how many do I need?


International Standard Book Numbers are used by publishers and booksellers to identify books and ebooks. Without them, it can get confusing to:

  • Correctly record and analyse sales data for different books, different editions, different volumes etc.
  • Prepare marketing materials with links to a book or ebook prior to publication
  • Manage hundreds and thousands of books in databases of publishers, wholesalers, booksellers, bookstores, marketing agencies etc.

If you ensure that each unique edition of your book has its own ISBN the benefits include:

  • The publisher will be paid the correct amount for sales of the book
  • Libraries and copyright agencies will pay for registered uses of your content
  • Customers will be able to find out what version of the title they are purchasing
  • Libraries can store ebooks and stock printed books once rather than mistakenly buying the same title twice
  • Book retailers will list books correctly in their databases

The upshot of all of this is that the proper use of ISBNs provides a good foundation for the success of your book. Sure, Amazon is the biggest bookseller in the world and uses its own numbers (ASIN), but if you want your book to be used outside of Amazon, an ISBN is imperative. Even if not, we would still recommend it. If using our book distribution services, PublishMyBook.Online will not release any books for sale without an ISBN.

There are 13 digits in the modern ISBN and these numbers are codes for the major meta-data of the book, including title, edition, format, publisher and author.

I want to know more about what ISBN numbers consist of.

How many ISBNs are needed for one book?

At least two—one for the print edition and one for the epub. Publishers have freedom in deciding how to manage ISBNs, but we recommend having these two separate ISBNs so your book can be correctly identified for the purpose of sales, marketing and publishing project management.

Who owns an ISBN?

The publisher of the book will purchase a block of ISBNs from the agency within their country, such as Bowker, and choose from their list of numbers what ISBNs to allocate to what books.

Sometimes independent authors purchase their own ISBNs. If you’re going to distribute your own book, it’s better if you do this, however, we can also supply ISBNs if you do not have some already, or if you do not have enough. In this case, we are not becoming your publisher as such, but are assisting you to self-publish, but if you need to change any details about the book on the Bowker database in the future we will need to do it.

The owner of an ISBN is able to mark it as ‘out-of-print’ on the Bowker database, so it is important to only self-publish your book using an ISBN you own or that a publishing service such as PublishMyBook.Online has allocated to you.

If your book contains an ISBN for a publisher that is defunct, out of business or no longer has rights to your title, you should get a new ISBN before re-releasing your book. If you do not you may be at risk of there being a negative impact on book sales or you may be in breach of a contract you enter into with a bookseller directly.

What will it cost to buy an ISBN?

If you purchase your own ISBNs, you will be able to update the information on the Bowker site yourself. If you use one of our ISBNs, included in our charge is the time it takes to update the Bowker database (the ISBN register) with details of your book post-publication but, as mentioned earlier, we will need to do any updates if they required later. It is important to make sure the information on this site is accurate as this is a data feed that is used globally by booksellers and databases, so it is important to handle it properly.

We can also create a barcode image to go on the back of your book. If you buy your own ISBN you might also be convinced to pay more than you need to for the barcode image. Experienced book designers do not need this to be supplied by Bowker.

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