(This post was last published in November 5th, 2015. It has been updated for accuracy and completeness.)
Amazon uses ASINs to manage their ever-growing product catalog. These unique product identifiers are an important part of Amazon’s selling policies as they help shoppers find the items they want. If not used correctly, Amazon sellers can violate selling terms and even lose their eligibility on the marketplace.
To ensure you can list and sell your items on Amazon, this article details what Amazon ASIN numbers are, why they’re important, and how to find and identify your product listings with them.
What is an ASIN number?
So, what is an ASIN number anyway?
ASIN stands for Amazon Standard Identification Number. It’s a 10-charcter alphanumeric unique identifier that’s assigned by Amazon.com and its partners. It’s primarily used for product-identification within their product catalog. For books, the ASIN is the same as the ISBN number.
ASINs are only guaranteed unique within a marketplace. So, different national Amazon sites may use different ASINs for the same product.
Why Amazon ASIN are Important to Amazon and its Sellers
An Amazon ASIN is important to both Amazon and its sellers because an ASIN is used to reference catalog data, track inventory for products, and index catalog pages for search and browsing.
The ASIN number is the foundation of Amazon’s product catalog structure, which in turn gives shoppers advanced search options like drilling down through multiple categories. Shoppers can even type a product description or ASIN number into the search box to find the exact item they’re looking for. Using a product’s ASIN, Amazon delivers accurate, and relevant product searches every time.
It’s vital then that sellers identify and use the correct ASIN identifier for their products. Otherwise, Amazon won’t be able to organize and search your products for customers. So, if you want to list any product on Amazon, you must match your product to an existing ASIN number or create a new one.
How to Find Your Amazon ASIN Number
You can locate an Amazon ASIN number for your product in a few different places: product web address, product details, or a software tool for ASIN lookups.
The fastest way is to look in your browser’s address bar for the product you’re looking to sell. The Amazon ASIN will be after the product’s name and “dp”, as highlighted below.

The second place you can find the ASIN is in the product details on Amazon.com, near the bottom of the product’s page.

Sellers can also use software tools like Synccentric to perform ASIN number lookups. If you have thousands of products, you wouldn’t want to search web addresses for each item individually. Instead, you can use an online too to do a bulk upload of your product identifiers that returns each ASIN number.
Of course, these types of tools will cost you. Whether or not you need one will depend on the number items you have and how often you list new products to Amazon.
Note that it is prohibited to create a new ASIN for a product that already exists on Amazon. Doing so can result in your selling privileges being temporarily suspended or permanently removed. It’s important to check if your item is already on Amazon!
Product Variation Policy
While searching and adding ASIN numbers, Amazon sellers often deal with product variations, or parent-child relationships. Variations allow shoppers to compare and buy products based on different attributes like size, color, or other characteristics. Here’s how variations might look to an Amazon shopper:

For these products, there will be one parent ASIN number. However, Amazon has several rules about how to list variations. There are also several prohibited practices to prevent sellers from misusing variations and fundamentally changing children products and how they relate to their parent ASIN number.
Read more about Amazon Variation Relationships policies
Adding Unique Amazon ASINs: Using GTINs, UPCs, ISBNS, and EANs
If you’re adding a new item to Amazon, sellers must create a new ASIN to add it to the Amazon catalog. Manufacturers often have to add new ASINs for their products.
To create a new ASIN, Amazon provides an “Add a Product” tool. Once your product page is up, then you can sell your items. (Be aware that other sellers can also use this ASIN number to sell the same items.)
When creating a new ASIN, you’ll need to know your product’s GTINs, or Global Trade Item Numbers. The most common GTINs used are UPCs, ISBNs, and EANs. These types of product codes are generally found near the bar code on the product package of your product. Amazon uses these universal product identifiers to create and match their own unique ASIN codes.
- ISBN (International Standard Book Number): 10 digits or 13 digits
- UPC (Universal Product Code): 12 digits
- EAN (European Article Number): 13 digits
- GTIN-14 (Global Trade Item Number): 14 digits
If you don’t already know your GTIN, you can request it from the manufacturer of your product. But, if you manufactured the item yourself, you’ll need to register your product through the GS1 US for UPCs, or US ISBN Agency for ISBNs (for US sellers).
ASIN Creation Limit
Amazon does limit the number of new listings sellers can create based on sales history, listing creation history, and other factors. As you increase your sales, your capacity to create new listings will also increase. Amazon suggests to prioritize the products you are listing to increase your sales quickly.
Read more about Amazon’s ASIN creation limits.
Creating New Amazon ASIN Indicates Low Competition
Amazon continues to grow their extensive product catalog across hundreds of categories. However, that also means that Amazon has become an extremely competitive marketplace to sell on.
If your product requires you to create a new Amazon ASIN, this is an indication that you’re the only seller for the product. You won’t have to compete with any other direct sellers. This is a great strategy to help you win the Amazon buy box, which is a sure way to increase sales.
As you look to list new products on Amazon, keep in mind how competitive that item is. Are there already multiple sellers offering it or are you creating a new ASIN for it?
What to Do Next
Identifying your Amazon ASIN number is the first step in listing your products on Amazon. It’s important you understand the process to match or create your ASIN so your items are searchable for customers.
To learn more about selling on Amazon, check out these other popular articles:
- How to Sell on Amazon for Beginners Using FBA: A Step by Step Guide
- Amazon Buy Box: How Amazon Sellers Can Win the Buy Box
- Are Fulfillment by Amazon (FBA) Fees Worth the Cost?
- 10 Amazon Selling Tips All Sellers Need to Know
- Top 5 mistakes to Avoid When Selling on Amazon
- Amazon Product Listing Optimization Best Practices

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Here is a cool tip on how to locate an ASIN quickly. Thanks for the explanation as well 🙂 https://palletfly.blogspot.com/2016/09/amazon-tip-what-amazon-asin-is-what-its.html
here is a free tool to convert asin to upc,ean,isbn and more:
http://www.asinlab.com/
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