In one sentence
Query fan-out is when an AI search system splits one user question into several related sub-queries, runs them, and combines the results into one answer.
What it means
Google describes query fan-out as part of how AI Mode and AI Overviews work. Other assistants that search the web behave similarly. A single buyer question can become searches for comparisons, pricing, reviews and alternatives, and your page may be retrieved for one of those, not for the original question.
Do not confuse this with prompt fan-out, which is a Pineprompt term for the opposite side: expanding one topic into many realistic buyer prompts so tracking reflects real demand. Query fan-out happens inside the engine. Prompt fan-out is something you do.
What to do about it
Cover the adjacent questions around your main topic on your site: comparisons, pricing, limitations, alternatives, how-to. Pages that answer a narrow sub-question directly are more likely to be retrieved for it.
Also expect the sources cited to differ from the pages that rank for your head term. Look at what gets cited, not only at your own rankings, to see which sub-questions you are missing.
How Pineprompt measures it
Pineprompt cannot observe an engine's internal sub-queries. It tracks the prompts you set, generated with the prompt fan-out generator, and the sources each answer ends up citing.
Frequently asked
- What is Query Fan-Out?
- Query fan-out is when an AI search system splits one user question into several related sub-queries, runs them, and combines the results into one answer.
- How does Pineprompt measure Query Fan-Out?
- Pineprompt cannot observe an engine's internal sub-queries. It tracks the prompts you set, generated with the prompt fan-out generator, and the sources each answer ends up citing.