What Is the Difference Between Google AI Mode Fan-Out and Deep Search?

How do they compare?

Deep Search is also different from Deep Research in the Gemini app, which produces research reports inside Gemini rather than in Google Search. The idea behind fan-out is explained in what query fan-out is.

How many searches does Google AI Mode run for one buyer question?

Google says only that AI Mode issues “a multitude of queries simultaneously”. Outside estimates vary with the question:

• Ahrefs writes that AI Mode typically makes 5 to 11 searches for a question such as finding a red phone case.
• Research by Seer Interactive and Nectiv, as summarised by Ahrefs without naming the engine measured, found an average of 9 to 11 fan-out queries per prompt, with 59% of prompts triggering 5 to 11 searches, 24% triggering 12 to 19, and some reaching 28.
• Ambiguity drives the count. A vague question such as “best laptop” spreads into many interpretations; a precise one such as “14-inch laptop under $1,000 with 16 GB RAM for video editing” needs fewer.

For comparison, Ahrefs recorded ChatGPT's deep research running about 420 searches on the same phone case task. Deep Search sits in that research-tool range, with Google describing hundreds of searches per report.

What kinds of sub-queries does fan-out create?

Analyses of AI search, including Ahrefs' review of patterns identified from Google's patent applications, describe a few recurring kinds:

• Disambiguation: an underspecified question is split into its likely meanings, so “red phone case” becomes searches for several phone models.
• Related topics: subjects that give context, such as containers and recipes for a meal-prep question.
• Follow-up questions: the next things people usually ask, such as diagnosis and treatment after a symptoms question.
• Specifics and comparisons: prices, specifications, reviews and head-to-head checks for buying questions.

Buying questions tend to produce the last kind, which is why pages with clear prices, specifications and comparisons are pulled into answers so often.

Does personal context change the searches?

It can. Google said in 2025 that AI Mode would offer suggestions shaped by a person's past searches, and signed-in users may see answers tailored to them. Two people asking the same question may therefore trigger different sub-queries and see different sources. When you test, use a signed-out browser or a fresh profile, and repeat each question a few times before drawing conclusions.

What happens to your pages in each?

In standard AI Mode, each sub-query retrieves pages from Google's index using its core ranking systems. A page can be used because it answers one sub-question well, even if it does not rank for the whole question. To appear as a supporting link, a page must be indexed and eligible to show a snippet. Search Console counts an AI Mode impression when your link appears in the answer, and Google's help notes that AI Mode groups a question into subtopics and searches each at once.

In Deep Search, the wider sweep reaches more pages and more specialist sources: detailed guides, data pages, documentation and niche publications that a short answer would never need. Reports cite many sources, so a well-documented page on a narrow point has more chances to be included.

What does this mean for your content?

• Answer the sub-questions buyers have, such as price, compatibility, sizing, setup and alternatives, within strong pages. Do not create a separate page for every variation; Google's guidance treats that as scaled content abuse, as covered in whether scaled content can be penalised.
• Give each section a clear heading and a direct first sentence, so a sub-query can match a passage.
• Publish specifics: figures, comparisons, specifications and steps, which both short answers and long reports use.
• Go deeper on your core topics if your buyers do serious research, since Deep Search and similar tools read further than a normal answer.

How can you find the sub-questions for your topics?

Google does not show the searches AI Mode runs. You can approximate them:

1. Ask AI Mode your buyers' questions and note the subtopics its answer covers and the sources it links for each.
2. Look at People Also Ask and related searches, which reflect common follow-up questions.
3. Read long, question-style queries in Search Console for your pages.
4. Run buyer questions in batches and record which subtopics you are missing; some tracking tools also estimate fan-out queries.

Why Google offers limited reporting on this is covered in why there is no Search Console equivalent for AI visibility.

We have not measured AI Mode's fan-out ourselves. This page is based on Google's announcements and help pages, and published research by Ahrefs, Seer Interactive and Nectiv.

What might this look like in practice?

Consider an illustrative e-bike retailer, Rasknell Cycles, whose buying guide ranked well but was rarely linked in AI Mode. Running twenty buyer questions, the team saw AI Mode's answers cover range in cold weather, insurance, commuting tax schemes and battery replacement costs, none of which the guide addressed. They added a section for each to the existing guide, with figures and a short table, rather than writing new pages. Over the next two months, the guide began appearing as a link in answers about commuting e-bikes, and a customer who used Deep Search mentioned that the report had cited its battery cost table.

What do people ask about AI Mode fan-out and Deep Search?

Is Deep Search the same as Gemini Deep Research?

No. Deep Search runs inside AI Mode in Google Search; Deep Research is a feature of the Gemini app.

Can I see the fan-out queries for my topic?

No. Google does not show them. You can infer subtopics from AI Mode answers and related questions.

Do I need separate pages for each fan-out query?

No. Cover sub-questions within strong pages; a page per variation risks Google's scaled content abuse policy.

Who can use Deep Search?

Google AI Pro and AI Ultra subscribers in selected countries.