How to Get an ISBN Number for a Self-Published Book & Other FAQs

What is an ISBN number and why do you need one as a self-publishing writer? In this post, we will guide you through the process of purchasing an ISBN number, answering all your questions along the way.  

What is an ISBN number? 
An ISBN number (International Standard Book Number) is a sequence of numbers used to label a book within the categories of the retail publishing market.  Conventionally, this number sits above the barcode found on the back cover of a book.  
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What does an ISBN number look like? 
The ISBN number is made up of 5 sections. These individual sections represent the specifications used to identify the book. There are many resources out there that provide an in-depth anatomy of a 13-digit ISBN, but the basics are pretty easy to grasp (grab your nearest book and follow along!):   

• First section: Prefix number 

This element is 3 digits long and represents the European Article System (EAN for short). Essentially, the Prefix identifies the book within the global publishing market.  

• Second Section: Registration number 

Between 1-5 digits long, this element confirms the language, country or geographical area of the book. The Official ISBN Registration Group List allocates a unique Registration number to over 250 countries, languages and areas worldwide.  

• Third Section: Registrant number 

This element identifies the book’s publisher. Each publisher will have its own official Registrant number to represent its publications within the Registration Group.  

• Fourth Section: Publication number 

This element defines the book within the Registrant Group’s published titles. Stay with us, only one more section to go!  
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• Fifth section: The Check Digit 

This part does what it says on the tin and checks for any errors within the previous digits, for example, a mistyped number. Though some would say it is easily calculated, if like us you tend to stick to the literature side of things and avoid any mathematics with a barge pole, there are many Check Digit calculators to lend a hand.  
      
Why do I need an ISBN number? 
Libraries, wholesalers and distributors, all the way down to your small-town indie booksellers, will use it to distinguish your book among the masses. It isn't always compulsory, yet there are a few disadvantages to not having an ISBN where it isn’t an essential requirement, for example in the case of eBook publishing. However, in the case of printed books, you cannot sell a physical publication without an ISBN number. Without this form of identification, your book will be absent from numerous publication search engines that could significantly increase your exposure, such as the well-established Books in Print database. Overall, not securing an ISBN could have a large impact on your success as a self-publishing writer.