Unique Product Identifiers
How we de-duplicate products in marketplaces.
About unique product identifiers
Unique product identifiers (UPIs) define the product that you're selling in the global marketplace. They uniquely distinguish products that you are selling and help match search queries with your products. Unique product identifiers are assigned to each product by the manufacturer, so if you sell the same product as another retailer, the UPIs will be identical.
Common unique product identifiers include Global Trade Item Numbers (GTINs), Manufacturer Part Numbers (MPNs) and brand names. Not all products have unique product identifiers. However, if your product does have one, especially a GTIN, providing it can help make your listings richer and easier for customers to find. If your product doesn't have a UPI, you'll exclude it in your product data.
Guidance
Provide correct product identifiers (GTIN, MPN and brand) whenever possible. Do not make up, guess or include values from similar products. If you provide incorrect identifiers, your product(s) may be disapproved. Follow this guide to use unique product identifiers correctly and accurately:
- If your products have assigned unique product identifiers and you have them available: always include them to ensure best performance. If you have some identifiers available but not others, include what you have.
- If your products have assigned unique product identifiers, but you don't have them available: Leave the attribute blank – don't include incorrect identifiers (for example, internal SKUs or other values specific to your store) or identifiers from similar products.
- If your products don't have assigned unique product identifiers: Don't include them. Also do not include internal SKUs or other values specific to your shop in these attributes.
- If you're the manufacturer of a product (for example, custom or homemade goods) and you have no official brand, use your business name as the brand along with an MPN with a unique identifier number of your choice.
Deduplication
Depending on the information available, Axiom will group identical products together on the same product page. This allows the user to see all suppliers of a particular product or variant.
Tip
The selected supplier's product information (name, description etc.) will always be shown as provided by them.
- If a GTIN is provided for the product we will group it with other products using that exact GTIN.
- If no GTIN is provided we use AI to match the product to other products using the brand, MPN and product name.
Tip
The rest of this article explains the unique product identifiers that you may have to provide, how to troubleshoot issues with your identifiers and what to do if you don't have the identifiers.
Types of unique product identifiers
| Attribute | Code type | Where used | Format | What it is |
|---|---|---|---|---|
| GTIN | UPC | Primarily North America | 12 digits | Universal Product Code, also called GTIN-12 and UPC-A. A unique numerical identifier usually associated with a barcode printed on retail merchandise |
| GTIN | EAN | Primarily outside North America | Typically 13 digits, occasionally 8 | European Article Number, also called GTIN-13. A unique numerical identifier usually associated with a barcode printed on retail merchandise |
| GTIN | JAN | Japan only | 8 or 13 digits | Japanese Article Number, also called GTIN-13 |
| GTIN | ITF-14 | Global, on outer cases | 14 digits | GTIN-14, used on shipping containers and cases rather than the retail unit |
| MPN | MPN | Global | Alphanumeric, various lengths | Manufacturer Part Number. The number that uniquely identifies the product with its manufacturer. If you are the manufacturer and the only seller of a product without an assigned MPN, use a unique identifier number of your choice |
| Brand | — | Global | Text | The brand of the product. Should be clearly visible on the front of the product packaging or label. Sent as the brand field rather than as a code |
Every GTIN you submit is checked against the GS1 check-digit algorithm for its type, so a mistyped digit is rejected rather than stored. See Codes for the full list of accepted code types.
How to include unique product identifiers in your product data
Depending on the type of product that you submit, you'll submit different identifiers. For all of your items, we recommend submitting all three attributes (GTIN, brand and MPN) to help customers find your products.
Products with GTINs
For all widely manufactured products that have a GTIN assigned, submit the following attributes:
- GTIN
- Brand
- MPN
Products without a GTIN
If your products have an assigned GTIN, not submitting it can lead to limited performance. However, not all products have an assigned GTIN. In these cases, you don't need to submit a GTIN. You must still submit both the MPN and the Brand as these are required attributes, so must both be provided. If you don't have an MPN, the attribute can instead be a unique identifer number of your choice only if you are the manufacturer and only seller of a product. If you don't provide an MPN and Brand, we could reject your product.
Examples of products that may not have an assigned GTIN include:
- Shop-brand products
- Replacement parts
- Original Equipment Manufacturer (OEM) parts or replacements for OEM parts
- Custom-made products (custom t-shirts, art and handmade goods)
- Vintage or antique products
- Pre-order products
To help identify your products without a GTIN, you can use the MPN and brand attributes. An MPN, or Manufacturer Part Number, is a UPI for specific parts assigned by the manufacturer. The brand attribute allows you to use the brand of your product as a UPI.
Products without a brand
If the product has a clearly associated brand or manufacturer, submit the brand attribute.
If your product is custom-made, use your business name for the brand attribute.