Fan-out queries vs keywords: what is the difference?
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A keyword is a phrase people type into a search engine, counted month after month. A fan-out query is a search an AI assistant writes for itself while it answers one prompt, so it has no search history and often names things the assistant found seconds earlier. Ask the same prompt again and the queries can change.
Keyword research shows what people want and the words they use for it. Fan-out queries show the searches a page has to come up for before ChatGPT, Claude or Grok can cite it. Our guide to query fan-out explains how assistants split a prompt into searches. Below, we put the two side by side, using real queries recorded with Only Fan Out.
What is the difference between a keyword and a fan-out query?
People write keywords and tools count them over months. An assistant writes fan-out queries in a few seconds, for one answer, and builds some of them from pages it has just read.
| Keyword | Fan-out query | |
|---|---|---|
| Who writes it | People typing into a search engine | ChatGPT, Claude or Grok, while answering a prompt |
| Where you see it | Keyword tools, Search Console, autocomplete | Inside the assistant's response data, one turn at a time |
| Search volume | Measured every month | Most have little or none, Semrush says |
| Length | A few words | 61 to 90 characters was the most common length in DataForSEO's sample of 100,249 ChatGPT fan-outs |
| Stability | The same phrase from month to month | 27% repeated across runs of the same prompt in a Surfer test, and 66% showed up once |
| Settings | None, just the words | Search type, recency window, location, result count or search operators |
| Built from | What people already know to ask | The prompt, plus pages the assistant read earlier in the same answer |
What do real fan-out queries look like next to the prompt?
They are longer and more specific than the request, and two assistants given the same request write different ones. On 10 and 11 September 2026 we asked Claude and Grok to search the web and compare secondary maths tuition centres in Jurong East, Singapore, and recorded each turn with Only Fan Out.
| Engine and search | Query as the assistant wrote it | Words |
|---|---|---|
| Claude, places | secondary math tuition centre Jurong East Singapore | 7 |
| Claude, places | math tuition Jurong East MRT Singapore | 6 |
| Claude, places | tuition centre Jurong Gateway Road Singapore | 6 |
| Claude, web | secondary school maths tuition rates Singapore 2026 per hour tuition centre | 11 |
| Grok, web | secondary math tuition centres Jurong East Singapore | 7 |
| Grok, web | best secondary mathematics tuition Jurong East 2026 | 7 |
| Grok, web | Jurong East math tuition reviews fees classes | 7 |
| Grok, web | "Jurong East" "math tuition" OR "mathematics tuition" secondary OR O-level | 10 |
| Grok, web | The Math Lab Jurong East tuition | 6 |
| Grok, web | AGrader Jurong East secondary math fees class size | 8 |
| Grok, web | Zenith Education Studio Jurong East math tuition fees reviews | 9 |
| Grok, web | Matrix Math Jurong East fees class size reviews | 8 |
The request to Claude ran to 14 words. The two assistants wrote 12 searches between them, 6 to 11 words long, 7.7 on average, and no two were the same. Claude ran 4 searches and Grok ran 8, then opened 3 pages to read in full. Claude's first search and Grok's first search differ only by "centre" against "centres". A keyword tool would fold those into one keyword, but each was a separate search with its own results. Claude also wrote "centre" in its search though the request said "centers".
Why can't a keyword tool show you fan-out queries?
Many fan-out queries do not exist until the assistant has read its first results, and the rest change from one run to the next. Our recordings and two published studies show why.
- Some are built from results. Grok's first four searches were broad. Its next four each named one centre it had found, with "fees", "class size" or "reviews" added. A ChatGPT turn we recorded on 9 September 2026, for a local services search in Singapore, did the same: its second search step put three business names in quotes. No keyword database could hold those searches in advance.
- They add words the person never typed. Of the 12 tuition searches, 2 added "2026", 5 added fees, rates, class size or reviews, and Claude added a train station and a street name. In Ahrefs' study of 66.6 million ChatGPT responses, "2026" appeared in 17.6% of fan-out queries in August 2026 and 22.9% in September.
- They change between runs. In Surfer's 1,600 runs with Gemini, 27% of fan-out queries came back across repeated runs, 66% appeared once, and 0.6% appeared every time. One recording is a sample of what an assistant searches, not a fixed list.
What settings travel with a fan-out query?
A keyword is only words. A fan-out query can carry settings that change which pages come back, and none of them shows up in a keyword tool.
| Engine | Setting | What we recorded |
|---|---|---|
| ChatGPT | Search type | Web, business and image searches in one turn: 7 web, 7 business and 3 image across 3 search steps (9 September 2026) |
| ChatGPT | Recency window | A number of days on each web search: 30 on the first step, 365 on the later ones |
| ChatGPT | Location | Business searches carried "Singapore" in a field of its own, apart from the query words |
| ChatGPT | Bundled queries | One business line held three queries separated by semicolons |
| Claude | Result count | Its places searches asked for 8 and 6 results |
| Grok | Search operators | Quote marks and OR in one query |
The ChatGPT format above is the one we saw in August and September 2026, and OpenAI has changed it more than once this year. The recency window suggests a search can be limited to recent pages, so a page's date may decide whether it comes back at all. We have not tested how strictly ChatGPT applies it.
Does keyword research still matter for GEO?
Yes. Fan-out queries grow out of the prompt, and prompts come from the same people whose searches keyword tools count. DataForSEO found its fan-out queries shared 54% of their words with the prompt on average.
Keyword and Search Console data still tell you which topics have demand and which words people use. Fan-out data adds what they cannot show: the narrower searches an assistant runs on the way to an answer, including the ones that name a rival or carry a year, a price or a place.
How do you use fan-out queries and keywords together?
Use keywords to choose topics and fan-out queries to see what a page on that topic has to cover.
- Take the keywords you already track and write each one as the question a person would ask an assistant.
- Ask each question in ChatGPT, Claude and Grok, more than once, and record the queries with Only Fan Out.
- Group the queries by what they look for, such as a price, reviews, a place or a named rival, not by exact wording, since the wording changes between runs.
- Check each group against your pages. A group no page answers is a gap. A query that names a rival or a year your page leaves out is an edit.
- Use keyword and Search Console data to put the gaps in order of demand.
- Ask the same questions again after the changes and compare.
Our guide to GEO with fan-out data sets this out as a full workflow, from recording the queries to choosing what to fix first.
Related questions
Do fan-out queries have search volume?
Most have little or none in keyword tools, because an assistant writes them for one answer rather than people typing them month after month. Use them to find topics and the details people care about, not to measure demand.
Should I target fan-out queries as keywords?
Not word for word. In Surfer's test only 27% of fan-out queries came back across repeated runs of the same prompt, so target what a group of queries looks for, such as a price, reviews, a place or a comparison, rather than one exact phrase.
Do different AI assistants write the same fan-out queries?
No. When we gave Claude and Grok the same request in September 2026, Claude ran 4 searches and Grok ran 8, and none of the 12 queries matched another word for word.
See the fan-out for your own prompts
Only Fan Out is a free Chrome side panel that lists the queries, fetched pages and cited pages behind each ChatGPT, Claude or Grok answer. Nothing leaves your browser.
Add to Chrome, it's free