What is an ISBN? Do I need a 10 digit or 13 digit ISBN? I only have a 10 digit ISBN, what do I do?
An ISBN (International Standard Book Number) is a unique thirteen-digit item code provided by your country’s ISBN agency and assigned by publishers to identify the format and edition of a title.
EAN originally stood for "European Article Number," but has since been changed to "International Article Number." The term refers to the bar code used by retailers outside of North America.
Since a book already has an ISBN number to identify it, the EAN barcode for a book is then generated from the ISBN of the book. An ISBN and EAN are essentially the same.
A published book will have a different ISBN/EAN for each product type—one for the hardcover edition, one for the paperback edition, and one for the digital/ebook edition. Retailers and distributors require published titles to have an ISBN/EAN assigned to them for sales and inventory purposes.
More from ISBN.org: When participating in the ISBN standard, publishers and self-publishers are required to report all information about titles to which they have assigned ISBNs. For more than thirty years, ISBNs were 10 digits long. On January 1, 2007, the ISBN system switched to a 13-digit format. Now all ISBNs are 13-digits long. If you were assigned 10-digit ISBNs, you can convert them to the 13-digit format at the converter found at this website https://www.isbn.org/ISBN_converter
A 10-digit ISBN cannot be converted to 13-digits merely by placing three digits in front of the 10-digit number. There is an algorithm that frequently results in a change of the last digit of the ISBN.
Visit https://www.isbn.org/about_ISBN_standard to learn more about ISBNs and why they are needed.