Configuring product identifiers Brand, MPN, and GTIN/UPC Fields
Google requires at least two of the following three attributes for almost every product.
- Brand - brand name or manufacturer of the item
- MPN - manufacturer part number
- GTIN - global trade item number (UPC, EAN, JAN, or ISBN)
Background Info and Best Practices for GTIN/UPC
GTIN is the category (or hypernym) for UPC, GTIN, JAN, etc.
So UPC is a type of GTIN. Much more in-depth discussion is here: About unique product identifiers: Google Merchant Center Help.
Our 'aten_smart_gtin' field will find the right 'GTIN' from among all the relevant fields in your source data, which can be viewed from Manage Feed > Analyze Source Data page in your feed.
In case it finds multiple values, it assigns a weight to each one it finds and then chooses the one with the highest weight.
You can put the GTIN/UPC of the item into any of the UPC/GTIN-related fields and 'aten_smart_gtin' will find it, validate it, and insert it into the feed. It also validates the check-digits for UPC and EANs.
As a best practice, I recommend to enter all GTINs of any type into the GTIN field, and not use the UPC field since that is more limited in scope. For example, it would be confusing to put an EAN into the UPC field.
Tips
- Leave GTIN blank if it is not available.
- Not all items have a GTIN. For those items, leave the GTIN field blank and provide the brand and manufacturer part number (MPN) instead.
- GTIN is required for certain designated brands.
- For certain designated brands, you must provide a valid GTIN when the item condition is new.
- Specify MPN and Brand for items with no GTIN
- If the products are white-label, vintage, custom-made, or manufactured by you, then just set brand to your company name and map MPN to your internal product code or SKU field.
- Specify UPC codes as 12 digits
- To avoid an invalid identifier warning, always specify UPC codes as 12 digits. There should not be any hyphens/dashes or spaces in the UPC code, and remember to include any leading zeros.
- Use the complete Manufacturer Part Numbers
- Two or more character MPN values are now allowed. A single character MPN will result in an error.
- Use only one Manufacturer Part Number
- If the MPN has multiple variations of hyphenation, spacing, or capitalization, only specify the official or most common one.
- Use real, accurate information
- It is not useful to insert dummy, made-up, or generic values for these fields. You should only put information in these fields if it is real and accurate, otherwise, Google may suspend your items.
- Request exceptions for disallowed items
- If identifiers are not available for your products and Google disapproves the listings, then contact Google via your Merchant Center account to find out your options.
Looking up Identifiers
There are several ways to obtain the above information for your products.
- Search for the item in Amazon and look in the Product Information section.
- Contact or check the website of the item manufacturer or your supplier
- Read it off the product packaging
- Hire a Product Data Entry service
Multiple UPC codes
If you have multiple UPC codes for a single item, specify each one separated by a comma and space.
If you have products with size/color variations, each with a different UPC code, you have numerous options with varying complexity.
- Create a catalog field called 'upc' in your store catalog, and specify each UPC code separated by a comma and space.
- Create catalog fields called 'upc' and 'upc-multiple' in your store catalog, and specify just one of the UPC codes in 'upc', and all the UPC codes separated by commas in 'upc-multiple'. Google can accept comma-separated UPC codes, and for other shopping engines, you can use the single UPC code.
- With a Custom feed and some special programming, we can multiply your listings by each size/color option.
Fixing Google Merchant Center Diagnostic GTIN Errors and Warnings
Limited performance due to missing value [gtin] - Warning
Limited performance due to missing ISBN or GTIN - Warning
This warning is not something that can be fix via the feed. This is where Google expects the product to have a GTIN based on their master catalog. The only way to fix this is to contact Google and ask them how to remove the error. They may ask you to provide documentation stating that there is no GTIN for the products.
This warning typically affects a large number of items, but it does not prevent the listings from appearing in search results. Therefore, if the GTINs are difficult or impossible to obtain, the recommended action is to do nothing and ignore the warning.
Invalid GTIN - Error
Unsupported coupon value [gtin] - Error
These typically affects a small number of items. The recommended action is to review and correct these manually in your store catalog.
The feed automatically blanks out most invalid GTINs based on basic check-digit validation, but it doesn't catch every possible issue like reserved GTINs, internal company-specific GTINs, coupon code GTINs, etc.