Find out what are ISBN numbers is and why every author needs one to publish and sell books professionally.
If you’re an aspiring author or planning to self-publish your book, you’ve likely heard of an ISBN number. But what exactly is it, and why is it so important in the publishing world?
An ISBN (International Standard Book Number) may seem like just a series of digits, but it plays a critical role in identifying, distributing, and selling books worldwide. Whether you’re publishing an eBook, print edition, or audiobook, understanding ISBNs is key to making your book discoverable and professionally recognized.
What Is an ISBN Number?
An ISBN (International Standard Book Number) is a unique 13-digit identifier assigned to every published book or edition of a book. It serves as a universal product code that helps publishers, bookstores, libraries, and online retailers accurately identify and catalog your book.
Think of it as your book’s digital fingerprint, no two ISBNs are alike. Each format or version of your book requires its own ISBN. For example:
- Paperback edition → one ISBN
- Hardcover edition → another ISBN
- eBook (Kindle, EPUB, PDF, etc.) → separate ISBN
This ensures that each version can be tracked and sold independently through the global book distribution system.
Why Are ISBN Numbers Important?
An ISBN isn’t just a number, it’s a gateway to professional publishing. Here are some of the most important reasons every author needs one:
1. Enables Bookstore and Library Distribution
Without an ISBN, your book can’t be listed in databases that bookstores and libraries use to order and catalog titles. This means your book won’t be available through major distributors like IngramSpark, Barnes & Noble, or independent bookshops.
In short, no ISBN = limited visibility in both physical and online marketplaces.
2. Makes Your Book Discoverable Online
ISBNs make it easier for readers and retailers to find your book. When someone searches for your title or author name, the ISBN ensures they land on the correct edition across platforms like Amazon, Apple Books, and Google Play Books.
This unique identifier eliminates confusion, especially if multiple authors have similar titles or names.
3. Simplifies Inventory and Sales Tracking
For retailers, ISBNs are crucial for managing inventory and tracking sales data. For authors and publishers, they make it easy to:
- Monitor book performance
- Collect accurate sales reports
- Manage reprints or updated editions
Essentially, the ISBN is what allows your book to function like a commercial product within the global supply chain.
4. Establishes Professional Credibility
Books without ISBNs are often viewed as amateur or unofficial publications. Having one signals professionalism and shows retailers, libraries, and readers that your book is properly registered and ready for distribution.
Even for self-published authors, using an ISBN demonstrates commitment to quality and helps your book stand out in a crowded marketplace.
5. Ensures Ownership and Control
When you purchase your own ISBN, you retain full publishing rights and control over your book’s metadata, such as title, author name, publisher imprint, and pricing.
If you use a free ISBN from platforms like Amazon KDP, that ISBN technically belongs to Amazon as the publisher. While this may not affect sales, it can limit your flexibility if you later want to publish through other distributors.
Owning your ISBN means you are the official publisher of your work.
Do Self-Published Authors Really Need an ISBN?
Yes, especially if you plan to sell your book outside a single platform. Some self-publishing services, like Amazon Kindle Direct Publishing (KDP), allow you to sell eBooks without an ISBN, since Amazon uses its own internal tracking number (ASIN).
However, if you plan to:
- Publish a print book
- Distribute your work on multiple platforms
- Sell to bookstores, libraries, or universities
Then having an ISBN is essential. It ensures your book is recognized globally and available through professional retail channels.
Where Can You Get an ISBN Number?
ISBNs are assigned by official agencies designated in each country.
- In the United States, ISBNs are purchased through ISBN Services.
- In the UK, they’re obtained from Nielsen ISBN Agency.
- In Canada, ISBNs are free and provided by Library and Archives Canada.
You can buy a single ISBN or a block of them if you plan to publish multiple books or editions.
Conclusion
An ISBN number is more than just a publishing formality, it’s your book’s key to legitimacy, visibility, and global distribution. For self-published authors, owning your ISBN gives you full control over your publishing rights and ensures your work is recognized in the professional book market.
Whether you’re releasing your first novel, a non-fiction guide, or an eBook series, don’t skip this crucial step. Investing in an ISBN means investing in your author brand and long-term publishing success.