Is AEO Real? What 5 AI Engines Cite When You Ask (Study of 144 Answers)
Reddit accounted for a minority of skeptical-question sources in Gemini and Perplexity and none in the other engines, while other publishers dominated most engines' skeptical source mixes. ChatGPT was the exception, with vendor sites accounting for 82.1% of its skeptical source mix. Across 144 answers to 30 questions about AEO/GEO, brand visibility and citation patterns differed by both engine and question framing.
Reddit's share of Gemini's skeptical source mix was the highest among the engines, but remained below other publishers at 86.2%.
Vendor sites accounted for 82.1% of ChatGPT's skeptical source mix, compared with 79.1% for believer / how-to questions.
Believer / how-to answers contained 55 distinct brands, compared with 33 in skeptical answers and 28 in neutral definitional answers.
All engines named a common brand in 80.0% of skeptical questions, compared with 40.0% of believer / how-to questions.
Gemini had the highest overall share of citations appearing in Google's top 10 results, at 12.4%.
Skeptical answers mostly cited publishers, not Reddit
The study tested whether skeptical AEO/GEO questions would cite Reddit and forum sources at least twice as often as how-to questions, which were expected to cite agency and tool-vendor blogs instead. By that relative measure, Gemini (13.8% versus 6.4%) and Perplexity (5.0% versus 0.0%) met the twofold threshold for Reddit, while ChatGPT, Claude and Grok cited no Reddit sources under either framing. Even so, Reddit did not dominate either engine's skeptical source mix.
Other publishers accounted for 93.0% of Perplexity's skeptical source mix, 88.5% of Claude's, 86.2% of Gemini's and 65.0% of Grok's. ChatGPT, Claude and Grok each recorded a 0.0% Reddit share for skeptical questions.
For a business seeking visibility in skeptical answers, these results argue against treating Reddit as the default channel. Publisher coverage deserves attention, but the data do not identify which publisher formats or placements earn citations. Forums are not broken out separately, so the broader forum hypothesis remains unresolved.
Who AI recommends, by group
Skeptic framing
Believer / how-to framing
Neutral definitional framing
ChatGPT and Grok cited vendors more for skeptical questions
ChatGPT relied heavily on vendor sites even when questions expressed skepticism: vendor share was 82.1% for skeptical framing and 79.1% for believer / how-to framing. Grok also showed a higher vendor share for skeptical questions, at 35.0%, than for how-to questions, at 27.6%.
The pattern went the other way in Perplexity, where vendor share was 2.0% for skeptical questions and 26.0% for how-to questions. Gemini recorded 0.0% and 14.1%, while Claude recorded 7.7% and 13.9%.
Plan by engine. Audit whether your site and external coverage appear in each engine's answers rather than assuming that skeptical questions universally exclude vendor content.
How the groups compare
Questions where every engine named the same brand
How-to answers contained a broader set of brands
Believer / how-to answers contained 55 distinct brands across 46 answers. Skeptical answers contained 33 across 48 answers, while neutral definitional answers contained 28 across 50 answers.
Google led skeptical brand share at 52.1%. ChatGPT and Perplexity tied at 30.4% in believer / how-to answers, while Perplexity led neutral definitional answers at 36.0%. All engines named a common brand in 80.0% of skeptical questions and 40.0% of how-to questions.
For marketers, how-to questions are worth including in visibility audits because they surfaced a broader brand set in this sample. That is not evidence that a particular business has a higher chance of being recommended: brand presence does not establish endorsement, and the questions differed across framing groups.
Where AI gets its sources
Most cited sites
AI sources that also rank in Google's top 10
Search overlap and citation behavior varied by engine
The overall share of citations appearing in Google's top 10 results was 12.4% for Gemini, 6.3% for Perplexity, 5.9% for ChatGPT, 5.6% for Claude and 1.7% for Grok. For every engine, most cited sources fell outside Google's top 10 results in this sample.
The share of answers with citations also differed. Claude and Perplexity included citations in 100.0% of their answers, compared with 53.3% for Gemini. Yet Gemini averaged 5.3 brands per answer, compared with 2.4 for Claude and 1.7 for Perplexity.
Track brand appearances and source citations separately. An engine can name more brands while providing citations less often, and a search-ranking report alone would have missed most of the sources cited in these answers.
What this sample can establish
The dataset covers 30 questions across 3 framing categories and 144 answers from ChatGPT, Claude, Perplexity, Gemini and Grok. Grok contributed 24 answers; each other engine contributed 30. The framing groups also have unequal answer counts.
These findings describe this AEO/GEO question sample, not a trend over time or a result established across industries. They show differences associated with framing and engine choice, but do not isolate framing as the cause.
A useful business audit should separate skeptical, how-to and definitional questions, then record brand presence, citation sources and engine coverage. This dataset does not measure recommendation sentiment, resulting traffic or sales, or Google's own source mix by framing, so the hypothesis that Google shows a smaller framing gap remains untested.
Methodology
In October 2026 we asked ChatGPT, Claude, Perplexity, Gemini, Grok 30 buyer questions, split into 3 groups (Skeptic framing, Believer / how-to framing, Neutral definitional framing), through their APIs with web search on. Hypothesis tested: Skeptical questions about AEO/GEO will cite Reddit and forum sources at least twice as often as how-to questions, which will instead cite agency and tool-vendor blogs, and Google's top 10 will show a smaller gap between the two framings than the AI engines do.
Each engine was asked each question once. Brands named in each answer were extracted and normalized, cited links were grouped by site type, and Google's top 10 organic results were recorded for the same questions. Engines that failed to answer a question are left out of that question's numbers.
Download the data (CSV)Free to use with a link to this page.
FAQ
Should we prioritize Reddit to appear in skeptical AI answers?
Not on these findings alone. Reddit had a minority share in Gemini's and Perplexity's skeptical source mixes and a 0.0% share in the other engines. Other publishers dominated most engines' skeptical answers, while ChatGPT favored vendor sites.
Does appearing in Google's top 10 mean AI engines will cite us?
The data do not establish that probability. They measure the share of AI citations appearing in Google's top 10, which was low across the engines, not the likelihood that a ranking page receives an AI citation.
Do more brand mentions mean more recommendations?
No such conclusion is supported here. The statistics report brand presence and citation patterns, not whether mentions were favorable recommendations or whether they generated business outcomes.