A Shopify merchant is encountering Google Merchant Center errors: “Too many values (Size)” and “Invalid Value (Size)” for products with S, M, L variants. The user is unsure how to properly format the single Size field in Google Channel when multiple size variants exist.
Key Issues Identified:
The free Google Channel app doesn’t support assigning individual size values per variant
Material attribute is incorrectly formatted with commas instead of forward slashes
Multiple colors are being submitted when only one should be used per product
Proposed Solutions:
Use a paid data feed app that allows assigning specific attributes to each variant
Set up a feed rule in Google Merchant Center to extract size from product titles (since Google Channel automatically appends variant sizes to titles like “Red T-Shirt S”)
Fix material formatting to use forward slashes
Submit only one color per product listing
Feed Rule Setup Process:
Navigate to Google Merchant Center → Feeds → Content API feed → Feed Rules tab → Add rule selecting “title” as source and S, M, L as extraction values (case-sensitive). Test and activate the rule to resolve size attribute issues.
Summarized with AI on November 23.
AI used: claude-sonnet-4-5-20250929.
I’m troubleshooting settings to fix Google Merchant Center’s messages “Too many values (Size)” and “Invalid Value (Size)”. I’ve attached screenshots for visual reference. I’m set up Variants for just size values - typically S, M, L. In the Google Channel fields in Shopify there is one Size field and then you can put the various sizes in the Meta Size fields. My question is how to format the Size field in the Google Channel if there is just one field but three sizes? The SKU numbers for the variants are the same with the exception of a .S, .M, or .M after the SKU number. So for Small it would be SKU number of XXXXX.S for small.
Any suggestions on what I’m doing wrong? All products have an SKU number and Barcode #. Thanks in advance.
Right now it is the case that the Google Channel will append your size attribute to the product variant title.
For example:
Your name for the product is “Red T-Shirt” and you have the variants S, M and L for it. Then the Google Channel will export it as “Red T-Shirt S”, “Red T-Shirt M” and “Red T-Shirt L”.
You can check this in the Google Merchant Center. If it is the case you can set up a feedrule to extract the size value fromt the title.
To do that:
Visit the Google Merchant Center
Go to your feeds and click on your feed coming from the Google Channel app probably it’s name is “Content API”
Click on the tab “Feedrules”
Click add rule
Select the attribute you like to add to the feed in this case “size”
In the next step set up the filter by selecting “title” as source and add S, M and L each in a new line as values to extract
In the advanced settings you should also check the box to be case sensitive when you write the sizes in capital letters
Then save the rule as a draft
After saving it you can test your rule and activate it if everyting is allright
Hope this will solve your issues regarding the size attribute!
