Part 1 · Foundations · Updated September 13, 2026 · 6 min read
What is Generative Engine Optimization (GEO)? A Definition You Can Check
Definition
Generative Engine Optimization (GEO) is the practice of improving how often, and how favorably, AI engines such as ChatGPT, Gemini and Perplexity mention, cite and recommend a brand in their answers. Where SEO optimizes for a ranked list of links, GEO optimizes for a place inside the answer itself.
- GEO is about earning a place inside AI-generated answers, not on a page of links.
- The term comes from a peer-reviewed 2024 research paper, which found the right content changes can lift visibility in AI answers by up to 40%.
- GEO is not geo-targeting, not keyword stuffing, and not a one-time project.
- Because AI engines give different answers to the same question, GEO is as much a measurement discipline as an optimization one.
The shift GEO responds to
For twenty years, being found online meant one thing: rank on the page of links a search engine returns, then win the click. That model is being replaced in front of us. OpenAI reports that ChatGPT has more than 900 million weekly active users. Google says AI Overviews, the AI-written answers above its classic results, are used by over 2 billion people a month.
When a buyer asks one of these engines “what tool should we use for X?”, the engine does not return ten blue links. It writes an answer, and that answer names a handful of brands. Either you are one of them or you are not. There is no page two of an AI answer.
That is the problem GEO exists to solve: how does a brand earn, keep and measure its place inside answers it does not control?
Where the term comes from
Unusually for a marketing term, GEO has a precise birthplace. It was coined in the research paper “GEO: Generative Engine Optimization” by Pranjal Aggarwal and co-authors from Princeton University and IIT Delhi, published at KDD 2024, one of the main academic venues for data science.
The paper did three things that still shape the field:
- It defined the problem. The authors formalized the “generative engine”: a system that searches for sources, then writes a synthesized answer with citations. That covers ChatGPT with browsing, Perplexity, Google’s AI Overviews and AI Mode, and Copilot.
- It measured what works. The authors tested nine ways of rewriting the same content and measured how visible that content became in generated answers. Their headline: the right changes “can boost visibility by up to 40%”. The best-performing changes were adding quotations, adding statistics, and citing sources. Old-style keyword stuffing did not help, and on some engines it hurt.
- It gave the field a benchmark. GEO-bench, a set of 10,000 realistic queries, so later work could be compared fairly.
We cover the findings, and their limits, in chapter 4.
What GEO is not
Not geo-targeting. In advertising, “geo” has long meant location targeting. Same letters, unrelated discipline. Generative Engine Optimization is about AI answers, not maps.
Not keyword stuffing with new packaging. The tactic most associated with old SEO was measured directly in the founding paper and classified as non-performing. Repeating words does not persuade a system that reads for meaning.
Not a replacement for SEO. AI engines still lean on search and retrieval to find sources, so classic discoverability still matters. GEO extends SEO to a new surface; it does not delete it. The differences are the subject of chapter 2.
Not a one-time project. AI answers change between runs, between model versions and between months. A brand that “checked its AI visibility once” knows what one answer said one time. GEO in practice is a loop: measure, fix, re-measure.
One discipline, several names
You will also see AEO (Answer Engine Optimization), LLMO (Large Language Model Optimization) and “AI SEO”. These names describe the same discipline with different emphasis, and vendors tend to pick the one they can own. GEO is the name with the academic paper behind it and the widest adoption. We use GEO throughout this guide and treat AEO as a synonym; the differences that actually matter are between optimizing for rankings and optimizing for answers, not between the labels.
Questions people ask about this
What does GEO stand for?
Generative Engine Optimization: the practice of improving how often, and how favorably, AI engines such as ChatGPT, Gemini and Perplexity mention, cite and recommend a brand in their answers.
Is GEO the same as AEO?
In practice, yes. AEO (Answer Engine Optimization) is another name for the same discipline. GEO is the term introduced by the 2024 research paper that founded the field.
Does GEO replace SEO?
No. AI engines still retrieve sources through search, so classic SEO remains the foundation. GEO adds a new goal on top: being mentioned and cited inside the generated answer, not just ranked below it.
Why does GEO need repeated measurement?
Because the same question returns different answers run to run. One reading tells you what one answer said once; only repeated runs tell you how often you actually appear.
Sources
- Aggarwal et al., "GEO: Generative Engine Optimization" KDD 2024. The paper that coined the term and measured the first GEO methods.
- OpenAI, "Scaling AI for everyone" February 2026. ChatGPT: more than 900 million weekly active users.
- Alphabet Q2 2025 earnings remarks July 2025. AI Overviews: over 2 billion monthly users.