What ISBN Actually Does

For new authors, the term ISBN can be confusing. Why is it needed? What is it even for? Let this clear the fog.

What is an ISBN?

ISBN or International Standard Book Number is a 13-digit unique code of a particular book edition and a format (e.g., hardcover) of a book. Think of it as an identification number for books used to track the version and format of the book being circulated in bookstores, libraries, distributors, and retailers for ordering, stocking, or selling.

What is "not" an ISBN?

It is not a copyright. Having an ISBN does not mean the book is protected from any form of reproduction, replication, distribution, or printing. For a work to be legally protected from such, a copyright should be applied for. This is done separately by the publisher or the author.

What information is recorded with an ISBN?

Similar to a person's identification number, an ISBN record attaches metadata to your book, such as title, author's name, publisher on record, the version, and the publishing format. The metadata shows in the bookstore databases, library catalogues, and retailer listings.

Free ISBN vs. Purchased ISBN

If you are selling your book on Amazon KDP, IngramSpark, or other platforms, you will notice that they provide a free ISBN in case you don't have one yet. It's great that you don't have to spend on buying an ISBN. Honestly, it isn't a bad option if you're a self-published author on a tight budget, but before you go down that route, let me share the real tradeoff.

Registering your work using a free ISBN from a platform would automatically list the platform itself as the publisher on record. When your book is tied to the platform's ISBN, that can limit your ability to distribute the same edition elsewhere under your own imprint. This technically means the platform is your publisher.

In the United States, you need to buy your own ISBN to give you full ownership and control of your creative work. ISBNs are purchased through Bowker—the official ISBN agency. It is highly recommended to buy in bulk. Bowker sells a single ISBN, but the price per unit significantly drops when purchased in blocks of 10, 100, or 1,000. This is a much more practical approach, especially if you plan to publish your book in multiple formats. Moreover, if you plan to write more books, this is the most cost-effective strategy. 

How do you use ISBN?

A single ISBN covers exactly one format of one edition. That means: 

1. A paperback format needs an ISBN.

2. A hardcover format needs an ISBN.

3. An ebook format needs an ISBN.

In addition, if you release a new version, you need a new set of ISBNs if you decide to publish it in multiple formats. This rule also applies to every language translation, in every book format.

On the other hand, audiobooks are not required to have ISBNs. They are tracked separately through ASIN numbers in Audible and Amazon. But an author may opt to assign an ISBN to their audiobook. Hence, this might vary using other platforms.

In simple terms, ISBN is used to organize all the books released in the world. Therefore, getting an ISBN as an independent publisher or a self-published author will save you from so many troubles to prove that you are indeed the rightful owner of your own book.