Amazon ASIN, EAN, ISBN and UPC Explained

Amazon UPC

Guest post by Gabe from Synccentric

Did you know that every single product in the world also has its own identification numbers? As an online retailer, you may be faced with figuring out the differences between the identification number options and. With so many numbers to choose from that are associated with the same product it can be confusing to know which is the correct product code to use – Amazon ASIN number, EAN, ISBN or UPC?

Understanding when to use each number format and how to map each code back to the product so you can track your inventory and run the correct reports can be complicated. But it doesn’t need to be.

If you’re a third-party seller in need of a simple breakdown of the differences between Amazon ASIN, EAN, ISBN and UPC then keep reading for the information you need!

1. Amazon ASIN Number

Amazon ASIN

If you are planning on becoming an Amazon third-party seller or you already are, then ASIN is an important abbreviation as it is the Amazon Standard Identification Number. Because Amazon as a retailer is so vast, they need all their items to have their own number for their warehouses to recognize which products to sell.

ASINs are only universal when it comes to books. In this instance, Amazon uses the ISBN and ASIN interchangeably. But for other products, there could be a separate ASIN depending on your location. For instance, the same item in the United States may have a different ASIN than an identical item in the UK.

Every third-party seller is responsible for marking their inventory with the correct ASIN so that it will end up in the correct location. Finding an ASIN is easy if you search on Amazon. The ASIN will be in the URL of an item. If you are having trouble locating it, the item description will also have an ASIN listed in the details. You can even create a new ASIN if you have a unique item.

Coding each item may seem tedious, especially if it an item already labeled with a UPC but without the correct ASIN, your item would never navigate itself out of the warehouse and into the hands of your customers. Once you have a solid understanding of ASIN it will become easier to find things in the entire Amazon catalog.

Related: Action to Take When You Get an ASIN Change Notification

2. EAN


European Article Numbers are yet another way of distinguishing. EANs are used in a similar way to UPC, just commonly used in Europe over the United States. EAN is also overseen by GS1, but the format is slightly different for use in Europe.

The only major difference between UPC and EAN is that EAN has 13 digits and the information in the code is in a different order than a UPC. Depending on where an item is manufactured will decide which code it receives. UPC is used in the United States and Canada, where EAN is used everywhere else globally.



Just as products have a UPC code assigned to them, every book has an ISBN or International Standard Book Number. Every book, magazine and even ebook published needs to have an ISBN unless you are self-publishing. (And it’s possible to get an ISBN for self-published books as well!)

Every edition of a book will have a separate ISBN, even if it’s the same title. This delineation helps publishers and authors understand exactly how many books have been purchased and which areas of the world are purchasing the material. Each country has an agency to register the ISBN of new materials but they are held to an international standard.

4. UPC


Image credit: GS1-US

UPC is short for Universal Product Code. As the name implies, this is the number that is universal. No matter which retailer or marketplace you are using, this number will be recognized and associated with your product. This is the number that is used to make barcodes and will be used by the manufacturer to help understand how many items are sold worldwide.

A UPC is most typically 12 digits long. Those numbers reflect the size and weight of an item. UPC became popular as automated billing became more popular. Since retailers were no longer typing in the individual price of an item, they needed a way for checking out to go faster and for a computer to recognize what the item was.

The technology for UPCs hasn’t changed much since they were first invented. If you’ve ever done a self-checkout at a grocery or retail chain, you are scanning the UPC code, and that code tells the computer how much that item weighs so the “bagging area” will be able to recognize it.

If you have a brand new product with no UPC assigned to it, you will need to register your item with GS1, the company that oversees all UPC. Once your product has a code assigned to it, you can order as many barcodes as you need in order to label your items ready for sale.

How to Use Them

Keeping track of all the different numbers associated with an item may seem overwhelming but it doesn’t have to be. There are many tools on the market that can help you quickly keep track of all your items and their different identification numbers.

There are even converters available to use which can quickly and accurately assist you in taking an item’s ASIN and matching it with it’s UPC. These tools can help you run reports you need as a retailer. Don’t worry about needing to individually search for the number or worry about an error as you type each ASIN, these tools will keep track of your items for you.


You will need to know how all the numbers work, you will order from manufacturers with UPC or ISBN and sell on Amazon with ASIN. If you sell merchandise on other platforms your focus will be on UPC or EANs. It may sound confusing but over time you will discover that using these different numbers becomes second nature.

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