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Query Fan-Out
How Google's AI features break one search into several related sub-queries, fire them at once, and gather sources from the index to build a single answer.
What it is
Query fan-out is the technique Google's AI features use to answer a question. Instead of running your one search, the system silently splits it into several related sub-queries and fires them concurrently against the core search index. A question like "best CRM for a two-person agency" might fan out into searches for pricing, integrations, ease of use, and small-team reviews, all at once.
The results from those parallel searches are then pulled together, through Retrieval-Augmented Generation, into a single written answer. So a page does not get cited by matching your exact phrasing. It gets cited by matching one of the many sub-questions Google generated on your behalf. Google describes this directly in its AI features optimization guidance.
Why it matters
Fan-out changes what "ranking for a keyword" means. You are no longer competing for one query; you are competing for a cloud of related sub-queries you never see. The practical move is breadth and depth: cover the angles a real person would ask about, with clear sections that each answer a contained question.
It does not mean chopping content into tiny fragments or writing for the machine. Google's own advice is the opposite. Because fan-out runs over the regular index, the path in is the same as classic SEO: be crawlable, helpful, and well-structured. For more on how those parallel results turn into citations, see how AI Overviews pick their sources and our explainer on AI Overviews.
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