Amazon.com Help: Product Identifiers

International Standard Book Numbers (ISBNs), Universal Product Codes (UPCs), and European Article Numbers (EANs) are distinctive codes used to identify a particular item. We use these codes and numbers to identify the exact item you wish to sell. We further identify items in the Amazon catalog using an Amazon Standard Identification Number (ASIN).

How to Identify ISBNs, UPCs, EANs and ASINs

You will find the ISBN, UPC or EAN on the packaging and/or back cover of your item, and the Amazon Standard Identification Numbers (ASIN) on the page where the same item is sold at Amazon.com.

ISBN
Do not include hyphens when entering these numbers. However, if a 10-digit or 13-digit ISBN ends with the letter X, be sure to include the letter.

ISBNs are located above the bar code:

UPC
When entering a UPC, be sure to include the smaller numbers on the left and right sides of the bar code.

UPCs are found below the bar code:

EAN
When entering an EAN, don't include dashes between any of the 13 digits in the number.

EANs are found below the bar code:

Note: In many cases, Amazon.com carries only the latest version of a product. Older versions or editions may have different ISBNs, UPCs or EANs. As a result, you may be unable to find the exact item you have using the product identifier, even though a very similar item is listed on Amazon.com.

ASIN
Amazon Standard Identification Numbers (ASINs) are unique blocks of 10 letters and/or numbers that identify items. You can find the ASIN on the item's product information page at Amazon.com and in the URL for the page.

The quickest way to find your product's ASIN is to look in your browser's address bar. Copy the number that appears after the item name and "dp" in the address:

What are GTINs?

Global Trade Item Numbers (GTIN) are unique and universal identifiers used to find product information across databases. GTINs include ISBNs (International Standard Book Numbers), UPCs (Universal Product Codes), EANs (European Article Numbers). and JANs (Japanese Article Numbers).

The ISBN system, which was developed in the mid-1970s for books and book products, expanded in January 2007 to require a 13-digit code, most commonly called a Bookland EAN. The "ISBN-13" identifier is a subset of the EAN system.

In the Amazon catalog system, "ISBN-10" identifiers are regularly substituted for ASINs on book pages. When an ISBN-13 (EAN) is provided, however, the detail page will be given a unique ASIN consisting of 10 characters.

Standards for GTINs used in the Amazon catalog are listed below: