Knowledge base v2.13.0 · Community edition · data through 2 October 2026
Thing · Product
Google's tool where retailers submit product data (feeds) that Google Shopping, free listings and AI shopping experiences use.
Glossary · Merchant Center
Google's tool through which merchants send product data feeds for Shopping ads, Search ads and organic results. Products need it to appear in the Shopping tab; product rich results do not.
Documented in
Google's ecommerce documentation recommends linking from menus to category pages, from category pages to sub-category pages and from sub-category pages to all product pages; where not every product can be linked, it recommends a sitemap or a Merchant Center feed.
Google Search Central · Day 2 · Welcome to indexing day!
Google's documentation updates log calls the July 2026 sale price change a clarification: a new Sale duration section of the merchant listing guide explains validFrom with validThrough or priceValidUntil, aligned with Merchant Center's sale_price_effective_date attribute.
Google Search Central · Day 2 · What is Structured Data and why we need it on the internet.
Google's Product structured data introduction says that providing both on-page structured data and a Merchant Center feed maximizes eligibility for shopping experiences and helps Google understand and verify the data; product snippets may take pricing from the feed when the markup lacks it.
Google Search Central · Day 3 · How Search results are born
Google's Merchant Center help says products and details crawled from an online store can show up on Google even when they are not marked up with schema.org or added in Merchant Center, and lists the Shopping tab among the places Merchant Center free listings appear.
Google Merchant Center Help · Day 3 · How Search results are born
Merchant Center's automatic item updates use structured data and other product data found on landing pages to fix price, sale price, availability and condition mismatches in a merchant's product data; Google says they do not replace regular feed updates.
Google Merchant Center Help · Day 3 · How Search results are born
On 11 January 2026 Google announced 'dozens of new data attributes' in Merchant Center for conversational commerce on AI Mode, Gemini and Business Agent, to roll out first with a small group of retailers.
Google blog (11 January 2026) · Day 3 · Shopping on Search: Beyond the blue links
At Google Marketing Live on 20 May 2026 Google said retailers globally can now use conversational attributes in Merchant Center to reflect the more conversational way people search.
Google blog (20 May 2026) · Day 3 · Shopping on Search: Beyond the blue links
Google's Merchant Center help marks the question_and_answer, document_link, related_product and popularity_rank attributes as primarily intended for conversational experiences such as AI Mode in Google Search.
Google Merchant Center Help · Day 3 · Shopping on Search: Beyond the blue links
Merchant Center's question_and_answer attribute takes up to 30 question-and-answer pairs per product, each question and answer up to 1,000 characters and 10,000 characters in total, and must not contain prices, shipping, dates or the company name.
Google Merchant Center Help · Day 3 · Shopping on Search: Beyond the blue links
Merchant Center's document_link attribute takes up to five URLs of PDF documents about a product, such as manuals, user guides or assembly instructions, and the merchant must own the content licensing rights.
Google Merchant Center Help · Day 3 · Shopping on Search: Beyond the blue links
Merchant Center's popularity_rank is a 0-100 value the merchant assigns to rank a product's popularity, based on its recent sales, against the rest of its own inventory; it does not reflect user ratings.
Google Merchant Center Help · Day 3 · Shopping on Search: Beyond the blue links
Google's Merchant Center help says the StoreBot crawler goes through product detail, cart and checkout pages, can fill in checkout forms, and records price, shipping, availability, coupons and payment methods to verify the data merchants share in Merchant Center.
Google Merchant Center Help · Day 3 · Shopping on Search: Beyond the blue links
Merchant Center's product_highlight attribute takes 2 to 100 highlights of up to 150 characters each that describe only the product itself, without promotional text, keywords or search terms.
Google Merchant Center Help · Day 3 · Shopping on Search: Beyond the blue links
Merchant Center's product_detail attribute takes up to 100 specifications, each a section name, attribute name and attribute value, and Google's help says clean key-value specifications improve product details on Google Shopping and AI-driven surfaces.
Google Merchant Center Help · Day 3 · Shopping on Search: Beyond the blue links
Slide and stage claims that name it, the ones Google’s documentation does not cover first.
Google's Merchant Center feed specification is how millions of merchants send Google billions of product offers, which are used in Shopping ads, Search ads and organic search results.
Alex Jansen · Day 3 · Shopping on Search: Beyond the blue links
A recent schema.org release added two properties, specification and valueGroup, so that the Merchant Center product detail attribute can be expressed in schema.org, with product specs nested under specification.
Alex Jansen · Day 3 · Shopping on Search: Beyond the blue links
Product annotations on Google Images results also come from product structured data and do not need Google Merchant Center.
To appear in the Shopping tab of Google Search, a product must be submitted in Google Merchant Center; product structured data alone is not enough.
In 2026, a few months before the October event, Google added new Merchant Center feed attributes to help AI systems understand product nuances, prompted by feedback since 2025 from merchants worried whether AI experiences represented them correctly.
Alex Jansen · Day 3 · Shopping on Search: Beyond the blue links
Google named the Universal Commerce Protocol (UCP), next to the Merchant Center feed, as an industry standard whose capabilities it also wants schema.org to cover.
Alex Jansen · Day 3 · Shopping on Search: Beyond the blue links
Google Search displays product rich results from product structured data; it may also use the product data a merchant provides in Google Merchant Center, but Merchant Center is not required for them.
Product structured data can help Merchant Center in some cases, for example during data validation, but Merchant Center does not require it.
Google added six Merchant Center feed attributes for AI shopping experiences: question and answer, documents, related products, item group title and variant option for variants, and popularity rank.
Alex Jansen · Day 3 · Shopping on Search: Beyond the blue links
Google now emphasises two existing Merchant Center attributes for AI, product highlights (a short bulleted list) and product detail (detailed specifications), and updated its Help Center guidance to say they help AI systems.
Alex Jansen · Day 3 · Shopping on Search: Beyond the blue links
Google Shopping pointed to a Google holiday shopping blog post with early results from real merchants using the conversational attributes, and to the Merchant Center Help Center and schema.org for the attributes and properties.
Alex Jansen · Day 3 · Shopping on Search: Beyond the blue links
For time-limited sales, give the sale price its validity dates in the product markup (Google's merchant listing documentation describes validFrom, validThrough and priceValidUntil) instead of editing markup by hand when the sale ends, and keep the dates aligned with the Merchant Center feed.
Ibrahim Anjro · Day 2 · What is Structured Data and why we need it on the internet.
Google's free listings help says crawled store products can appear on Google without markup or Merchant Center but does not say whether that includes the Shopping tab; for a shop that wants Shopping tab visibility, the stage rule that Merchant Center is required is the safe working assumption.
Ibrahim Anjro · Day 3 · How Search results are born
For an online shop, Product structured data is enough for product rich results and Google Images product annotations, but the Shopping tab needs a Merchant Center feed too; keep feed and markup values identical, since Google can use the markup to validate the feed.
Ibrahim Anjro · Day 3 · How Search results are born
Google's January 2026 announcement spoke of 'dozens' of new Merchant Center attributes, while the Day 3 talk counted six; all six named on stage (question_and_answer, document_link, related_product, item_group_title, variant_option, popularity_rank) are in the Merchant Center product data specification as of 3 October 2026.
Ibrahim Anjro · Day 3 · Shopping on Search: Beyond the blue links
As of 3 October 2026 Google's Merchant Center help lists no schema.org property for question_and_answer, document_link, related_product, popularity_rank, variant_option or product_detail (only item_group_title maps, to ProductGroup.name), and Search Central does not document such markup: reading these attributes from schema.org is a stage statement, the feed is the documented route.
Ibrahim Anjro · Day 3 · Shopping on Search: Beyond the blue links
Shop developers should first keep core feed and markup values (price, availability, brand, GTIN) accurate, then add Q&As, product highlights, specs as key-value product details and related products in the Merchant Center feed, and mirror them in schema.org Product markup only as Google documents support for it.
Ibrahim Anjro · Day 3 · Shopping on Search: Beyond the blue links
Kit items about Merchant Center: their own words name it, or several of the claims they rest on do.
Rests on 13 claims, 8 of them naming Merchant Center; its own words name Merchant Center
Rests on 9 claims, 7 of them naming Merchant Center; its own words name Merchant Center
Mark up merchant listings completely, with validity dates for sale prices
Rests on 7 claims, 2 of them naming Merchant Center
Treat product Q&A and specification markup in schema.org as an extra on top of the feed
Rests on 6 claims, 2 of them naming Merchant Center; its own words name Merchant Center
Also inglossary terms Conversational attributes, Merchant Center, Product highlights and product details, Universal Commerce Protocol (UCP)
To appear in the Shopping tab of Google Search, a product must be submitted in Google Merchant Center; product structured data alone is not enough.
Things named in the same claim, with the number of claims they share.