Where do the terms GEO and AEO come from?
The term AEO came out of the late 2010s, when Google's featured snippets and voice assistants such as Alexa and Siri began reading out one answer instead of a list of links. A featured snippet is the boxed answer Google shows above its regular results. Answer engine optimization is the practice of shaping a page so an engine can lift that one answer from it: a tight paragraph, a list or a table that matches the question exactly.
The term GEO came from the 2023 research paper GEO: Generative Engine Optimization by Aggarwal et al. (Princeton University, Georgia Tech, the Allen Institute for AI and IIT Delhi), presented at the KDD conference in 2024. Generative engine optimization is the practice of shaping a page so engines that write their own answers can find, trust and cite it. The authors wrote that, with generative engines, "content creators have little to no control over when and how their content is displayed." Their study tested nine ways of rewriting a page, and the authors state that the approach can "boost visibility by up to 40% in generative engine responses."
How do GEO and AEO differ side by side?
GEO and AEO differ mainly in what the engine returns: AEO targets one extracted answer, while GEO targets a written answer that cites several sources at once.
| AEO | GEO | |
|---|---|---|
| Built for | Featured snippets, voice assistants, “People also ask” | ChatGPT, Perplexity, Gemini, Claude, Google AI Overviews and AI Mode |
| What the engine returns | One extracted answer, often read aloud | A written answer that cites several sources |
| How you win | Be the single best match for the question | Be one of the few sources quoted and linked |
| How you measure it | Snippet ownership, voice answer checks | Citation rate across real prompts, and a GEO Score for readiness |
What do GEO and AEO have in common?
GEO and AEO have almost all of their tactics in common, because both reward pages that an engine can read, trust and quote quickly. Both favour a page that puts the answer in the first sentence under a question heading, keeps each passage readable on its own, backs its claims with named sources, and serves its text in the HTML rather than after JavaScript runs. Both also reward structured data, which Google's documentation explains this way: "Structured data is a standardized format for providing information about a page and classifying the page content" (Google Search Central). A page built well for one is built well for the other, and Google says the same of its own AI features: "There are no additional requirements to appear in AI Overviews or AI Mode, nor other special optimizations necessary" (Google guidance, 2025).
Does GEO replace AEO?
GEO does not replace AEO; it widens the target from the one answer an engine extracts to the several sources a written answer cites. Featured snippets still exist, and one well-built page can win both. What has changed is how often the answer ends the search: Similarweb data shows zero-click searches rose from 56% to 69% between May 2024 and May 2025, and an ALM Corp analysis reports that 83% of searches end without a click when AI Overviews appear, and 93% in AI Mode.
Which AI engines does GEO target?
GEO targets the AI engines that write an answer and cite their sources: ChatGPT search, Perplexity, Gemini, Claude, and Google's AI Overviews and AI Mode. Each of them reads the web with its own search crawler. OpenAI's crawler documentation says that "OAI-SearchBot is used to surface websites in search results in ChatGPT's search features", and these crawlers are busy: a Vercel analysis counted 569 million GPTBot requests across its network in one month in 2024.
How do you measure AEO and GEO results?
AEO and GEO results are measured differently: AEO by whether your page holds the featured snippet or the voice answer for a query, GEO by your citation rate across a panel of real questions. According to the GeoTest glossary, a citation rate is "the percentage of category-relevant prompts that surface a site as a cited source." Readiness is measured separately: a free Quick Scan scores one page in about 15 seconds, and a Site Analysis scores up to 200 pages.
Do B2B buyers use AI answers to research suppliers?
B2B buyers do use AI answers to research suppliers, which is why both AEO and GEO now matter to business sites. G2's Answer Economy research, published in 2026, found that 71% of B2B software buyers rely on AI chatbots for software research. A buyer who gets a shortlist from ChatGPT or Perplexity may never see a results page, so the sources named in that answer are the ones still in the running.
Which term should you use, GEO or AEO?
Use whichever term your buyers search for, since GEO and AEO describe the same daily work in 2026. GeoTest uses GEO because today's engines generate their answers rather than extract them, and because citation, not position, is what a page can now win. The stakes are the same under either name. A Pew Research Center study of 900 people in the US found that 58% of them ran at least one Google search in 2025 that produced an AI summary, and that users who saw one clicked a traditional search result in 8% of visits, against 15% for users who did not. Clicks on a link inside the summary itself happened in just 1% of visits, according to the same report. The What is GEO guide covers the full method, and the GEO glossary defines every term used here.
