Structured data is markup built into the code of a web page, used to provide bot-friendly page data (and product data on e-commerce product pages). Search engines (like Google) use structured data to understand the content of the page, as well as to gather information about the page that are included in the markup.
In the context of Google Shopping feed, Google bots regularly crawl structured data of a product (by following the submitted product link in product feed) to cross-check it with the data provided in the product feed (price, availability, etc.). If they find mismatches, Google Merchant Center will raise mismatch errors.
For more information about how Google use structured data, click here.
A popular tool to check and validate structured data is Google structured data testing tool. You need to submit the URL of the website and the tool will list the structured data that it finds.
Most themes (free and paid) provided on Shopify store have structured data built in. However you might find your theme lacked structured data, especially if the theme is home-built, or has been customized.
You can use an app on Shopify store or edit the theme files to add the missing structured data.
Common errors of incorrect structured data includes:
1/ Incorrect product price value and/or price currency
If the product link supports pre-selected currency (Shopify Payments support pre-selected currency with a currency parameter attached to the URL, e.g. ¤cy=GBP), when the customer follows the product link, the currency is pre-selected on the product page, and the structured data needs to show the price value and currency sign of this currency.
The price value needs to be aligned with the pre-selected currency of the product page, and use dot as the decimal point.
For foreign currency feeds, the Multifeed Google Shopping Feed app automatically adds the currency parameter to product link.
2/ Incorrect pre-selected variant in structured data
For multi-variant product, most Shopify themes allow a variant to be pre-selected on the product page by a variant parameter in the product link. When the link is followed, the variant will be pre-selected with correct options and prices.
The offer in structured data needs to list the data only for this pre-selected variant.
We have seen structured data created by some apps and themes list the structured data of all variants. Since Google bots pick the first offer in the list (which corresponds to the first variant), other variants will suffer from mismatch errors.
Example of a pre-selected variant that suffer from mismatch error
It is because the underlying structured data is listing all variants data, starting from the first which is lower-priced than then pre-selected variant.
