Every item you sell on Amazon (or eBay, or anywhere else) will have a unique identifier that tags it as an individual product. But with so many names — ASIN, ISBN, SKU — keeping track of how and where to use each one can get confusing. Luckily, FeedbackExpress is here to help you keep track of your inventory no matter which product identifier is being used.

What is a Barcode?

You might know that series of vertical black stripes as a barcode, but it has a technical name: Global Trade Item Number (GTIN), which is a scannable symbol that brings up all sorts of information about the product unique and specific to it.

Back in ye olden days, it was enough to hand-write a sign that belonged to a product and call it a day. But with global commerce and so many products, a better system was needed and barcodes filled that need. They allowed for inventories to be organized in such a way that human error was reduced, less money was spent on the process, and uniform regulations were met.

But there’s not just one barcode — or GTIN — and that can make it hard to keep track of organizing your inventory, especially when dealing with different suppliers from around the world. There are multiple types of GTINs, so let’s dive in and see what distinguishes one from another.

International Standard Book Number

An International Standard Book Number (ISBN) is the barcode that’s attached to books, CDs and DVDs on Amazon. This 10- or 13-digit number is essential for being able to sell these items on Amazon (or list your self-published book on there), and there are a number of ways to get one.

The main way is with Bowker, probably the biggest company responsible for giving out ISBNs. Amazon can assign you an ISBN, but one thing to note is that if they do, it will only work with them. Regardless of whether you go through Amazon, Bowker or another party, once you have your ISBN, it can’t be changed after publication because that number is associated with the book’s trim size, title and author name.

Universal Product Codes

Universal Product Codes (UPCs) is an identification system that’s mainly used in the United States, Canada, Europe, Australia and New Zealand, although other places use it as well. This 12-digit number scans items at points of sale and originated from scanning grocery items in supermarkets.

Today, it’s grown to include all sorts of retail items and is subdivided into different codes based on label type. And to sell on Amazon, using a UPC is one of your GTIN options for identifying products. They’ll first search the UPC to find a match and merge product data if necessary; it not, you get a brand new product detail page.

European Article Number

A European Article Number (EAN) is a type of UPC and is also used for products scanned at points of sale. You can use this on Amazon, but make sure it’s not attached to an invalid product EAN listing or else it will be removed and you could face account suspension or removal.

Japanese Article Number

The barcode that is the Japanese Article Number (JAN) started out in 1978 and was made to be compatible with EANs, which meant attaching a flag number (either 49 or 45) to it. It’s a 9-digit number  (7 digits plus the flag code) and operates the same way on Amazon as UPCs, ISBNs and EANs.

Amazon Standard Identification Number

The Amazon Standard Identification Number (ASIN) might be the one you’re most familiar with, as it’s Amazon’s own barcode system that’s unique to their marketplace. It’s a 10-digit alphanumeric code that identifies specific products on Amazon and only Amazon.

Note: Making things interesting is that ASINs exist within geographic Amazon marketplaces, so you could very well have different ASINs for the same product on different marketplaces.

Stock Keeping Units

Last but not least you have Stock Keeping Units, otherwise known as SKUs. It’s a number you use for your own inventory to keep track of it, and how you do so is up to you. Because you’ll be dealing with it on a regular basis, come up with a system that’s straightforward and makes sense.

For example, you might want to start your SKU with a letter that represents the product’s name or category, followed by a number that indicates when you sent the item into Amazon, and so forth.

How to Get and Use Barcodes

Sometimes, you’ll either have an item that doesn’t have a barcode, might want to bundle things together and will need a barcode for the bundle, are selling private label brands, or are selling rare or collectable items. For the latter two cases (private label, rare or collectable), you might be allowed to list the items with publisher information or manufacturer model and part numbers instead. But you’ll have to apply for GTIN exemption through Amazon if that’s the case.

In almost all other cases, though, you’ll need some form of a barcode. As mentioned early on, Bowker is your best bet for obtaining ISBNs, but there are other companies that also deal in barcode generalities.

BarCodes Talk is one of the biggest names out there, which offers digital delivery of UPCs and EANs at no extra cost. Barcodes start at $5 each, but the more you buy, the cheaper each individual barcode gets.

Something to note is how barcodes are placed on products. Usually, they’re built right into the product packaging, so if you sell items that still need to be manufacturer, send the barcodes over to the manufacturer so they can incorporate it when making the product and its design.

Final Thoughts

Although there are plenty of different forms of barcodes, understanding what each one does helps simplify using them on Amazon. And though they’re not required in 100% of cases, they are used in the vast majority of scenarios and mastering the art of barcoding helps make your job easier.

While you’re taking the time to learn everything there is to know about barcodes, let the automation of FeedbackExpress keep things running in the background so you don’t have to worry about it. Every time you UPC or EAN, it’ll send out templated messages to buyers, helping increase your review count and leverage that into future sales.

Not convinced? Sign up now to get a 30-day free trial and you’ll be a convert by the end of it.

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