What is an ASIN?

An ASIN stands for Amazon Standard Identification Number. It’s a unique identifier assigned by Amazon to products in its catalog. Each product sold on Amazon has its own ASIN, which helps Amazon identify and manage its vast inventory. ASINs are used to search for items on Amazon and are crucial for product listings, sales, and inventory tracking on the platform.

Why are Amazon ASINs important?

Amazon is one of the fastest-growing and largest marketplaces in the world and carries over 12 million individual products.

When you also include products sold by third-party sellers that increases to more than 353 million, an eye-watering range of inventory.

Due to this expansive catalog Amazon needs a system to manage and identify each individual product quickly: enter the ASIN number.

Unique ASIN codes for each product mean Amazon sellers and support alike can quickly understand which specific product is being referred to at any time.

Should I create a new ASIN or use an existing ASIN?

Whilst the question of creating new ASINs creates some confusion for new Amazon sellers (we’ve all been there!), once you understand the basics of how the Amazon catalog works it becomes much clearer.

Unlike other marketplaces such as eBay, each unique product should only ever have one listing and therefore one ASIN.

For example, if you have 100 sets of the game Monopoly that you want to sell on Amazon you can’t just create a new listing for that.

Instead, you need to enter the existing product identifier code (eg: UPC, EAN… more on those in a minute!) to check if an ASIN exists, and if it does, attempt to sell your stock on that existing listing.


Just because it exists doesn’t mean you will be able to sell that product.

There may be some brands that don’t allow you to sell their products on Amazon as they have decided to be the only seller of an ASIN.

When should you create a new ASIN?

As a private label Amazon seller who is looking to sell their own brand of products on Amazon, you will always be creating new products.

This is another potential area of confusion as new sellers may be attempting to launch a product that is similar to other products available but under their own brand.

For example, you are launching a black yoga mat.

There are already hundreds of other black yoga mats for sale on Amazon and so you may be unsure as to whether yours is a product that isn’t already being sold on Amazon.

However, if you have added your own branding to this product then it is unique, and you should therefore create a new ASIN.

When should you use an existing ASIN?

If you are selling an existing product that you have sourced wholesale or as part of your retail or online arbitrage efforts and the product already exists in Amazon’s catalog then you will need to use an ASIN that exists already.

How do I create an ASIN on Amazon?

If you’re unsure if the product you’re looking to sell already has an ASIN number, then the first thing to do is head to Seller Central, access the Inventory menu and select Add a Product.

Next, enter one of the following product identifiers:

  • UPC: A UPC is a Universal Product Code and is 12 digits long. It is primarily used in North America.
  • EAN: An EAN is a European Article Number that is usually 13 digits long and is primarily used outside North America.
  • ISBN: An ISBN is an International Standard Book Number, is 13 digits long and is a product identifier used by publishers, libraries, booksellers and online retailers.

What is a GTIN?

A GTIN is a Global Trade Item Number, developed by the international barcode organization GS1, is the overarching term for product identifiers.

UPC and EANs are the most common types of GTIN and are the only ones an Amazon seller should be concerned about.

If you don’t know your GTIN, you can either look at the number below the barcode on the product or contact the manufacturer.

If you manufactured the product yourself under your own brand name then you will need to set the GTIN with your own GS1 account.

Once you’ve entered the product identifier into Amazon, if nothing comes up it means you’ll need to create a new listing and therefore a new ASIN number.

There are two ways you can do that, so let’s take a look at both.

Create an Amazon ASIN in Seller Central

This is the simplest way to create a new Amazon ASIN for beginners. Here are the steps to take:

  • Navigate to the Inventory menu
  • Choose Add a Product
  • Click ‘I’m adding a product not sold on Amazon’
  • Choose the relevant category
  • Input key info (UPC/EAN, Title, Description, Images)

As you add more information to the listing Amazon will open up more sections that need filling in before you can save.

Once you’re done, hit save and you’ve created your first Amazon ASIN!

Create an Amazon ASIN with an inventory upload file

Amazon’s bulk upload functionality is a steep learning curve and is not recommended for creating your first Amazon ASIN.

However, it is a skill that can come in very handy down the line if you want to upload or manage a large number of ASINs at once.

It can also prove very effective at updating existing listings when the often clunky Seller Central system gives errors or fails to properly update key information such as product title.

To create an Amazon ASIN code with an inventory upload file, head to the inventory menu and select Add Products via Upload.

You will need to download the right template based on your category and fill out the key information as instructed.

Here’s a helpful tutorial that walks you through the process:

Can 2 products have the same ASIN number?

No, multiple products having duplicate ASINs would defeat the point of each product having its own unique ASIN codes.

Amazon’s ASIN creation policy strictly forbids sellers from creating new listings and duplicate ASINs for items already in Amazon’s product catalog structure and doing so may put your selling privileges at risk.


Brand owners can protect their own ASINs from being duplicated by other sellers by enrolling in Brand Registry.

Is ASIN the same as SKU on Amazon?

No, an ASIN number is automatically generated by Amazon when a new product listing is created, whereas a SKU can be set by the seller themselves.

What is a SKU?

A SKU (pronounced “skew”) or Stock Keeping Unit is a number assigned by a retailer to a product in order to manage and track inventory.

They usually contain descriptive information about a product including color, size, style etc. For example, a blue yoga mat sold by ACME inc. may have the SKU ACMEYMAT-BL.

A SKU is not universal across all platforms and is rather set by the retailer. This differs from an ASIN because you have control over it.

As you grow your business beyond just selling on Amazon your SKU structure becomes more important as it helps identify inventory across multiple platforms.

When creating a new ASIN, Amazon will auto-generate the ASIN number but you will have the opportunity to set your own SKU.


We would advise brand owners to plan their SKU structure in advance and have these ready to go when creating a new ASIN, otherwise if left blank this field will auto-populate with random numbers and letters.

What is an FNSKU?

Fulfillment Network Stock Keeping Unit (FNSKU) is an Amazon term to describe the barcodes it uses to identify and track products across its fulfilment centres and connect specific inventory to specific sellers.

It looks similar to a standard UPC but is only used within Amazon’s network.

The use of FNSKUs is not always mandatory – some sellers can use the manufacturer’s barcode (EAN or UPC), but this can result in commingled inventory.

How do I find my Amazon ASIN?

Once you’ve seen an Amazon ASIN once, you’ll quickly start getting the hang of spotting them. Here are a few ways you can quickly and easily find an Amazon ASIN.

Find an ASIN via the Amazon URL

Navigate to a single product detail page and look in the browser’s address bar.

You’ll find a 10 digit string starting with B right after the product name and “/dp/” in the title. See an example in the image below.

The ASIN for this example product is B07SM25CXH.

Find an ASIN via the product detail page

On the product details page, scroll toward the bottom to find the product information table. Here you’ll find information such as product size and weight, amount of reviews, and of course Amazon’s ASIN.

Find an ASIN using a third-party software tool

There are a number of tools that fast-track the process of finding ASINs, but perhaps the easiest and quickest is the Helium 10 Xray tool.

Once you install the Chrome extension you’ll see a new widget over each product in search results showing key metrics. One of those? You guessed it, the product’s ASIN.

If you want to find existing Amazon ASIN numbers for a number of products you can fire up X-Ray to get a full list of search results or the ASIN Grabber to get an even simpler set of results.

Find an ASIN inside Seller Central

It’s easy to find the ASIN number for one of your own listed products. Just head to the Inventory menu inside your Seller Central account and choose ‘Manage Inventory’.

You’ll find a list of your products, and under the title will be the given ASIN.

What are Parent & Child ASINs?

You might have heard the terminology parent ASIN, child ASIN, or parent-child relationships with regards to listings on Amazon. But what exactly are these?

A parent ASIN is simply the parent product in a parent/child relationship. The parent acts as a placeholder under which the child variations are kept.

A child ASIN is a unique variation of a product that is linked to other child ASINs all sitting under one parent.

A simple example of this parentage structure in our beloved yoga mat example could see the ACME Yoga Mat as the parent ASIN, whilst the blue, red, and yellow versions would each be unique listings and therefore have their own ASIN.

As they live under the structure of the parent they would be referred to as child ASINs.

Customers wouldn’t be able to buy the parent listing as it is just a placeholder and instead would buy one of the child listings.

Here’s a diagram of what this structure can look like:

And here is an example of what child variation listings look like on Amazon:

What is Amazon’s Product Variation Policy?

Above all, Amazon is interested in creating a good shopping experience for its customers.

The parent/child variation structure is not created to help sellers launch products easier but to make buying choices easier.

Amazon, therefore, gives this guidance in its terms of service:

“Good variation relationship listings allow buyers to compare and choose products based on different attributes such as size, color, or other characteristics from the available options on a single product detail page.”

When deciding on whether to create a child ASIN or a parent ASIN, consider these guidelines. Is it an obviously similar product that only differs in size, color, or some similar attribute?

If so, list it as a child by adding a new variation in your inventory manager. If not, add it as a new parent listing.

Amazon ASIN FAQs

There is no given numerical limit by Amazon, but rules do state that your ASIN creation capacity does have limits.

If you try to create more listings than Amazon deem healthy they will put a limit on your abilities to list new ASINs and review your limits on a weekly basis.

The name Reverse ASIN Lookup could be a little confusing – don’t expect to use this to find ASINs!

Reverse ASIN lookup tools are types of Amazon seller tools that allow you to enter the ASIN of a product and find out what keywords they are ranking for.

This is a powerful feature of Helium 10’s Cerebro tool that can help you carry out fast, accurate keyword research.

ASINs can be found in the URL of each product. For example, this is the URL for a Monopoly set on Amazon with the ASIN highlighted – https://www.amazon.com/Monopoly-Family-Board-Players-Tokens/dp/B0B5HLZ8T4/

Yes, every product on Amazon has an ASIN as this is what helps Amazon identify each product from the next.


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