Every product on Amazon has one. Here's where it hides, and why it's the fastest way to look up a product anywhere.
Stuart Miles Posted
An ASIN is Amazon’s internal product number. Ten characters, letters and digits, unique to one product on one marketplace.
If you work with product data at all you’ll end up needing them, and they’re easier to find than most people expect.
Where to find an ASIN
Two places, and the first is faster.
In the URL. Open any Amazon product page and look for /dp/ in the address. The ten characters straight after it are the ASIN. Everything after that is tracking and can be ignored.
In the product details. Scroll down the listing to the product information table. It's listed there as ASIN, alongside the dimensions and the date first available.
Books are the exception. For anything with an ISBN, the ISBN-10 is the ASIN.
What an ASIN is not
It isn’t a universal product identifier. An ASIN belongs to Amazon and only to Amazon, and the same product carries a different ASIN on each marketplace — the UK number is not the US number.
If you want an identifier that works across retailers you want an EAN, UPC or GTIN. Those are assigned by the manufacturer and follow the product wherever it’s sold.
This matters more than it sounds. Build a system around ASINs and you’ve built a system that only understands Amazon.
Using an ASIN to find a product elsewhere
A good product database will take an ASIN and give you back the same product at every other retailer stocking it — which is the useful trick, because you generally start with an Amazon link and want to know who else sells the thing.
With the Squirrel API that's one call. Pass the ASIN in the code parameter and you get the product, the current price, the RRP, a commission-ready link and every other offer for it. The quickstart has the exact request.
The same field accepts UPC, EAN and SKU, so you don’t need to know which kind of identifier you’re holding.
If you’re getting your data from Amazon directly
Worth knowing before you build anything on it: Amazon retired the Product Advertising API in May 2026, and its replacement requires ten qualifying referred sales in the trailing thirty days before it will grant access. The full story is here, but the short version is that a new site cannot get Amazon product data at all.
ASINs still work as identifiers. Getting Amazon to tell you anything about them is the part that closed.
Where to go next
If you're looking up products in bulk, the API reference covers batching, webhooks and price alerts. If you'd rather not write code, the widget does the same job on the page.
Common questions
What is an Amazon ASIN?
A ten-character identifier Amazon assigns to each product. It appears in the product URL after /dp/ and in the product information table on the listing.
Where do I find the ASIN on Amazon?
In the URL, immediately after /dp/. Or scroll to the product information section of the listing, where it’s shown alongside the dimensions.
Is an ASIN the same as an EAN or UPC?
No. An ASIN is Amazon’s own number and differs between marketplaces. EANs and UPCs are assigned by the manufacturer and work across all retailers.
Is the ASIN the same in the UK and the US?
No. Each Amazon marketplace assigns its own ASIN to the same product.
Can I find a product at other retailers using its ASIN?
Yes, through a product database that maps identifiers across retailers. The Squirrel API takes an ASIN and returns every retailer stocking the same product.