In short. Query fan-out runs related searches across subtopics to gather information for a response.

Definition: Query fan-out is a search technique that breaks a question into related subtopics, runs searches for those subtopics in parallel, and combines the retrieved information into a response. Google describes this process in its AI Mode announcement.

Key facts

As of 17 October 2026, Google's AI features documentation says AI Overviews and AI Mode may use query fan-out across subtopics and data sources.
Google's AI Mode launch post, dated 5 March 2025, describes related searches running concurrently and their results being combined into an answer.
Google's May 2025 explanation describes splitting the user's question into subtopics before issuing searches simultaneously.

How does a question become multiple searches?

Google's launch example uses this question:

what's the difference in sleep tracking features between a smart ring, smartwatch and tracking mat

The example has a shared comparison task, sleep tracking, and distinct device categories. It illustrates why a multi-part question can require information about several subjects within the same response. Google's account connects concurrent searches across related subtopics with the combination of their results into an answer.

The May explanation also describes subtopic searches running on the user's behalf. In this process, the original question supplies the task, while the system breaks it into topics to search. A single submitted question therefore leads to multiple retrieval requests, meaning requests to fetch relevant information.

What does this change for a website?

A page must be indexed and eligible for a Google Search snippet, the short preview accompanying a result, to qualify as a supporting link in these AI features. Google's website guidance also calls for important content to be available as text.

The same guidance says special schema.org structured data is unnecessary. Structured data is markup describing page content for machines. The practical starting point remains a page that meets Search's eligibility requirements and presents its information in accessible text.

How is the resulting traffic measured?

Google's website documentation places AI feature traffic within Search Console's Performance report under the Web search type.

The Search Console measurement guide counts a click when someone follows an AI Mode link to an external page. When a person asks a follow-up question, the guide attributes the new response's impressions, positions and clicks to that new user query. This provides a specific distinction for reporting: the follow-up question has its own query attribution, even though it continues the conversation.

FAQ

How many searches does query fan-out run?

Google's 20 May 2025 announcement says Deep Search, its research capability in AI Mode, can issue hundreds of searches. These sources do not specify a fixed count for every ordinary AI Mode request.

Does my follow-up question count as another query?

Yes. Google's Search Console guide assigns the impressions, positions and clicks from the follow-up response to the new user query.

Sources

Check how a page reads to answer engines. Open the GEO score analyzer