GLOSSARY

Query Fan-Out

IN ONE SENTENCE

Query fan-out is when a system decomposes one user question into several sub-queries, retrieves for each, and then composes an answer.

Query fan-out is when a system decomposes one user question into several sub-queries, retrieves for each, and then composes an answer.

01

In detail

Google's own guidance names it alongside RAG as how AI Overviews and AI Mode work. The implication for content is that a page need not answer the whole question — being the best answer to one sub-query is enough to be used, which favours pages focused on a single issue over sprawling long-form.

Updated 2026-08-06