GEO optimizes content so it can be retrieved and cited by generative AI engines, ChatGPT, Gemini, Perplexity, Copilot, when they build their answers. Appearing in the results is not enough: you need to be inside the answer the AI generates.
The essentials in 30 seconds
- GEO means optimizing to be cited within the answers of generative AI engines, not to rank in a list.
- The term comes from an academic paper (Princeton et al., KDD 2024) that showed visibility gains of up to ~40%.1
- The techniques that help most: citations, statistics and sources. Superficial SEO tactics (keyword stuffing) do not work.1
- Ranking in Google’s top 10 no longer guarantees being cited by AI; the overlap is only partial.7
What GEO is
GEO (Generative Engine Optimization) is the practice of making a brand’s content fit to be retrieved, cited and referenced by generative artificial intelligence systems when they build their answers. Instead of a list of links, these engines produce a synthesized answer drawn from several sources, and GEO aims to ensure the brand is among those sources.
GEO aims to make the brand a source that AI models consider reliable and relevant enough to use and cite in their answers.
The origin of the term
Unlike many marketing terms, GEO has a precise academic origin. It was coined in the paper “GEO: Generative Engine Optimization”, by Aggarwal and colleagues (Princeton, Georgia Tech and Allen Institute for AI), presented at the KDD 2024 conference.1 The authors created GEO-bench, a set of roughly 10,000 queries, and tested nine optimization techniques.
The central conclusion, stated in the paper’s own abstract, is that GEO methods can increase a source’s visibility in generative answers by up to 40%.1 Equally important: effectiveness varies by domain, which reinforces the need for sector-specific optimization.
Why GEO matters
Part of search has migrated into conversations with AI assistants. Adoption is already widespread: according to Pew Research, 34% of US adults have used ChatGPT, about double the figure in 2023.8 And referral traffic coming from LLMs is growing fast: Search Engine Land reports average growth in the order of 80% between the two halves of 2025, with ChatGPT accounting for the vast majority of that traffic.10
GEO vs SEO and AEO
The three disciplines share foundations, but have different targets.
| Dimension | Classic SEO | GEO |
|---|---|---|
| Goal | Rank (position in the SERP) | Be cited/synthesized in the answer |
| Unit | The page | The extractable statement/sentence |
| Signals | Backlinks, keywords, CTR | Citations, statistics, clarity, source authority |
| Metric | Position, organic traffic | Citation rate / share of voice in AI answers |
| Bot access | Googlebot | GPTBot, PerplexityBot, ClaudeBot, OAI-SearchBot… |
AEO sits between the two: it focuses on answers extracted by the search engine (snippets, voice). In practice, AEO and GEO share the same foundation, extractable, structured and factual content, differing in the target “engine”.
How sources are chosen
Generative systems combine the model’s knowledge with retrieval of up-to-date information from the web. When they answer with sources, they tend to favor content that is clear and well structured, that addresses the topic in a specific and well-supported way, that comes from reputable sources and that is aligned with the question. Content that states concrete facts, cites data and identifies its authors is more easily reusable and attributable.
A revealing data point: Ahrefs found that only around 38% of the pages cited in AI answers were also in the organic top 10 for the same query, a decline compared to earlier periods.7 In other words, ranking well helps, but it is no guarantee of citation.
What works (and what doesn’t)
The Princeton paper measured the effect of each technique. The ones that most increased visibility in generative answers were:1
| Technique | Reported effect |
|---|---|
| Adding quotations/quotes from sources | The most effective (~+41% on one metric) |
| Including concrete statistics | Strong increase (~+31%) |
| Citing sources explicitly | Among the best |
| Improving fluency/clarity | Among the best, especially combined with data |
| Keyword stuffing / superficial SEO tactics | No effect (or negative) |
Citable: “According to Semrush’s study (2025, more than 10 million keywords), AI Overviews appeared in around 16% of Google searches.”, self-contained, with source, number and date.
Non-citable: “AI summaries show up in many searches these days.”, vague, with no source or data.
Brand authority and entity
Models reflect what is widely present and well referenced on the web. For this reason, GEO benefits from a consistent presence beyond your own site: brand mentions in reference sources, participation in recognized publications, and coherent information about the brand across different platforms. The more consistently a brand is described in reliable sources, the more likely it is to be associated with the right topics and cited accurately.
Technical access for AI
To be used by generative engines, content has to be accessible to their crawlers. Here there is a crucial and often misunderstood distinction: not all AI bots serve the same purpose.
| Type | Examples | What blocking implies |
|---|---|---|
| Model training | GPTBot, Google-Extended, ClaudeBot | The content is not used for training, with no direct impact on being cited in real time |
| Real-time search / answering | OAI-SearchBot, Perplexity-User, Claude-SearchBot | Removes eligibility to be cited in answers |
Blocking the search/answering crawlers (not the training ones) eliminates any chance of being cited in AI answers. The decision to allow or block is strategic and should be weighed up brand by brand.
Example of a robots.txt that allows the main AI crawlers:
# Permitir crawlers de pesquisa/citação de IA
User-agent: OAI-SearchBot
Allow: /
User-agent: ChatGPT-User
Allow: /
User-agent: PerplexityBot
Allow: /
User-agent: Perplexity-User
Allow: /
User-agent: Google-Extended
Allow: /
Sitemap: https://answer-layer.com/en/sitemap.xmlBeyond access, important content should be served as readable HTML (server-side renderable), and not depend exclusively on script execution. Official crawler documentation: OpenAI2, Google3, Anthropic4 and Perplexity5.
How to measure results
GEO measurement is still maturing, but there are indicators and tools:
- Citation rate / share of voice in AI answers, by engine and by topic.
- Sentiment of mentions and which URLs/sentences are cited.
- AI crawler hits in the server logs.
- LLM referral traffic in Google Analytics 4.
Monitoring tools include Otterly.ai, Profound and the AI modules from Semrush and Ahrefs (Brand Radar), which track mentions in ChatGPT, Perplexity, Gemini, Copilot and AI Overviews. AI answers are non-deterministic, so monitoring has to be continuous.
Common myths and mistakes
“GEO is just SEO rebranded.” No, the overlap between sources cited by AI and the organic top 10 is only partial.7
“Keyword stuffing helps with AI.” The paper shows the opposite: superficial tactics do not increase (and may reduce) visibility.1
“Blocking GPTBot has no cost.” It depends which bot: blocking the search ones removes eligibility for citation.
Practical GEO checklist
- The content makes self-contained statements, with numbers, dates and sources.
- It includes citations and statistics, the most effective techniques according to the paper.
- It is structured (descriptive headings, lists, tables) and well written.
- AI search crawlers have access (robots.txt) and the content is server-side renderable.
- The brand has consistent presence and mentions in external reference sources.
- Presence in AI answers is monitored continuously.
Frequently asked questions
Is GEO the same as SEO?
No, but they are closely linked. SEO optimizes for traditional search results; GEO optimizes to be cited by generative AI engines. Both rely on clear, reliable and accessible content, but the overlap between the two is partial: ranking well helps, without guaranteeing citation.
Which techniques really increase AI citation?
According to the academic paper that coined the term, the most effective are adding quotations/quotes from sources, including concrete statistics and citing sources explicitly, as well as improving the clarity of the text. Superficial SEO tactics, such as keyword stuffing, do not work.
Should I allow AI bots to access my site?
It is a strategic decision, but it is worth distinguishing training crawlers (GPTBot, Google-Extended, ClaudeBot) from search/answering crawlers (OAI-SearchBot, Perplexity-User). Blocking the latter removes any chance of being cited in real-time answers.
How do I control what AI says about my brand?
Not directly, but you can influence it: publishing clear and reliable content, keeping consistent information about the brand in reference sources and continuously monitoring mentions all increase the likelihood of an accurate representation.
Sources
- Aggarwal et al.: “GEO: Generative Engine Optimization” (Princeton/Georgia Tech/Allen Institute, KDD 2024). arxiv.org/abs/2311.09735
- OpenAI: GPTBot and bots (user-agents). platform.openai.com
- Google Search Central: Google crawlers / Google-Extended. developers.google.com
- Anthropic: ClaudeBot and crawlers. support.anthropic.com
- Perplexity: PerplexityBot and Perplexity-User. docs.perplexity.ai
- Semrush: AI Overviews Study (2025). semrush.com
- Ahrefs: AI search vs. organic overlap / citations. ahrefs.com
- Pew Research Center: 34% of US adults have used ChatGPT (2025). pewresearch.org
- Gartner: Search engine volume to drop 25% by 2026 (estimate). gartner.com
- Search Engine Land: What 13 months of data reveals about LLM traffic. searchengineland.com
Note: the per-technique gains from the paper are controlled laboratory values; market shares and the Gartner forecast are estimates that vary by methodology.