How to Find a Book's ISBN Number

What is an ISBN?

An ISBN (International Standard Book Number) is a unique numeric identifier assigned to each edition and variation of a book. Think of it as a book's fingerprint - no two editions share the same ISBN.

ISBNs are used worldwide by publishers, booksellers, libraries, and online retailers to identify and catalog books. When you search for a book by ISBN, you'll find the exact edition you're looking for.

ISBN-10 vs ISBN-13: What's the Difference?

You'll encounter two ISBN formats:

Most modern systems accept both formats. ISBN-13 always starts with 978 or 979. The hyphens are optional and used only for readability.

Finding ISBN on Physical Books

For printed books, check these locations:

1. Back cover - Look above or near the barcode. The ISBN is usually printed alongside the barcode.
2. Copyright page - Inside the book, typically on the back of the title page. You'll find the ISBN along with publisher information.
3. Inside the barcode - The barcode itself encodes the ISBN-13. The numbers below the barcode are the ISBN.

Finding ISBN for Ebooks

Ebooks can be trickier since you can't flip to the back cover. Here's how to find them:

• Check the product page on the retailer's website (Amazon, Kobo, etc.)
• Look in the ebook's front matter or copyright section
• Search the retailer's metadata or "Product Details" section

Important: Some ebooks, especially Kindle exclusives, may only have an ASIN (Amazon Standard Identification Number) instead of an ISBN.

Finding ISBN on Online Retailers

Amazon

On any Amazon book page, scroll down to "Product Details" or "Product Information." You'll find both ISBN-10 and ISBN-13 listed there.

Bookshop.org

The ISBN is displayed in the book's details section, usually below the price and format options.

Barnes & Noble

Look in the "Product Details" tab on any book page. The ISBN-13 is listed along with other publication information.

Goodreads

Click "Book Details" at the bottom of any book page to reveal the ISBN along with page count and publication date.

ISBN Lookup Databases

If you can't find an ISBN through the methods above, try these free databases:

• 1
  Open Library

  openlibrary.org - Free, open-source library catalog with millions of books

• 2
  WorldCat

  worldcat.org - Global catalog of library collections

• 3
  Google Books

  books.google.com - Search by title and find ISBN in book details

What If a Book Has No ISBN?

Some books don't have ISBNs:

• Self-published books (though many do have ISBNs)
• Books published before 1970
• Some academic publications and journals
• Certain regional or small press publications

In these cases, you can use the author name and title to identify the book. BookBuzz supports both ISBN and author/title searches, so you can create recommendation links either way.