· AI SEO Fundamentals · 6 min read
GEO vs AEO: What’s the Difference, and Does It Matter?
GEO and AEO both describe optimising for AI-powered search, but they come from different eras and aim at slightly different wins. Here’s where they differ, where they overlap and what the research actually shows.
GEO vs AEO in one sentence each
AEO wins you the answer; GEO wins you a mention in the answer. Answer engine optimisation (AEO) makes your content the direct answer to a specific question. Generative engine optimisation (GEO) makes your brand one of the sources an AI tool cites or recommends when it writes a response.
The two terms are often used as if they mean the same thing, and in practice they overlap heavily. This guide explains where each came from, where they genuinely differ, and what the research says actually works.
What is AEO (answer engine optimisation)?
AEO is the older idea. It grew up alongside Google’s featured snippets, People Also Ask boxes and voice assistants, all of which pull a single answer from one page. Ahrefs first recorded searches for “answer engine optimisation” in March 2019.
Winning at AEO means being the page an engine lifts the answer from. That usually takes:
- a question-led heading that matches how people search
- a direct answer in the first sentence or two beneath it
- supporting detail, lists or tables underneath
- structured data where it accurately reflects the page
Our answer engine optimisation service covers this in depth.
What is GEO (generative engine optimisation)?
GEO was defined in a research paper. In November 2023, researchers from Princeton and IIT Delhi published “GEO: Generative Engine Optimization”, later accepted at KDD 2024, a leading data science conference. They defined a generative engine as a system that retrieves several sources and writes an answer from them, as ChatGPT search, Perplexity and Google’s AI Overviews do.
The phrase had started to appear in searches a few months earlier (Ahrefs first recorded “generative engine optimisation” in August 2023), but the paper gave it a definition and evidence. It went mainstream after investment firm Andreessen Horowitz published “How GEO Rewrites the Rules of Search” in May 2025.
Winning at GEO means being cited or named within an AI-written answer, often alongside competitors. See our generative engine optimisation services for how we approach it.
What the original GEO research found
The paper is the closest thing the field has to controlled evidence, and most GEO articles never mention its results. The researchers tested nine ways of rewriting content and measured how visible each made a source inside AI-generated answers. Scores are position-adjusted word count; the unedited baseline scored 19.5.
- Adding quotations: 27.8, the best result
- Adding statistics: 25.9
- Fluency improvements: 25.1
- Citing sources: 24.9
- Using technical terms: 23.1
- Easier-to-understand wording: 22.2
- More authoritative tone: 21.8
- Unique words: 20.7
- Keyword stuffing: 17.8, worse than doing nothing
Two findings matter most for smaller businesses:
- Old SEO habits can backfire. Keyword stuffing reduced visibility in AI answers below the baseline.
- The underdog benefits most. Citing sources increased visibility by 115.1% for the site ranked fifth in search results, while the top-ranked site’s visibility fell by 30.3% on average. When tested on Perplexity, a real AI search engine, adding quotations improved visibility by 22%.
In short, evidence-rich content gives lower-ranked businesses a real chance to be cited ahead of bigger names.
GEO vs AEO: side-by-side
The clearest way to separate them is by what “winning” looks like.
- Goal. AEO: be the single direct answer. GEO: be cited or recommended within a generated answer.
- Where it shows up. AEO: featured snippets, People Also Ask, voice assistants, AI Overviews. GEO: ChatGPT, Perplexity, Gemini, Claude, Google AI Overviews and AI Mode.
- What wins. AEO: a concise answer directly under a question-led heading. GEO: evidence (quotations, statistics, sources), clear brand facts and mentions on trusted sites.
- How you measure it. AEO: snippet and People Also Ask ownership, Search Console impressions. GEO: how often you’re mentioned across a set of AI prompts, plus AI referral traffic.
- Oldest use of the term. AEO: first recorded by Ahrefs in 2019. GEO: defined in a 2023 research paper.
Where GEO and AEO overlap
In practice, most of the work is the same. Even the UK’s communications regulator doesn’t split them: Ofcom describes ChatGPT and Google’s AI Overviews alike as “answer engines”, tools that “generate the answers themselves” rather than only pointing to web pages.
Both disciplines reward:
- answer-first writing: clear answers in self-contained sections
- evidence: specific facts, figures and credible sources
- entity clarity: consistent information about who you are and what you do
- technical access: pages that search and AI crawlers can reach and read
- trust: genuine expertise, reviews and mentions on reputable sites
In the UK, the search data shows which term has caught on. GEO searches (about 2,300 a month across both spellings) outnumber AEO searches (about 600) by nearly four to one, according to our Ahrefs data. Searches for “geo vs aeo” itself were first recorded only in February 2025.
How GEO and AEO relate to SEO
Think of SEO as the foundation, with AEO and GEO built on top. AI search tools still rely on pages that are crawlable, indexed, fast and trustworthy. Google’s AI Overviews draw on its search index, and ChatGPT search draws on web search results. If a page can’t rank or be crawled, it’s unlikely to be quoted.
What changes is the finish line. SEO aims for a position in a list of links. AEO aims for the answer box. GEO aims for a mention in a written response. Together, they’re often called AI SEO, which is the approach we take as an AI SEO agency.
Which should your business focus on?
Most UK businesses need both, but the balance depends on how your customers search. AI search is already mainstream here: Ofcom reports that about 30% of UK searches now show an AI Overview, 53% of adults see them often, and ChatGPT had 1.8 billion UK visits in the first eight months of 2025, up from 368 million a year earlier.
- Local and service businesses (trades, clinics, professional services): lean towards AEO and Google AI Overviews. Many of your customers still start on Google.
- Considered purchases and B2B: lean towards GEO. Buyers increasingly ask ChatGPT or Perplexity for a shortlist, and being named matters more than being linked.
- Already strong in SEO: do both. Your rankings give you a head start; the job is making your content easy to quote.
- Not sure where you stand: measure first. An AI visibility audit shows how AI tools answer your customers’ questions today.
How to measure AEO and GEO
Measure them differently, because they win in different places.
- AEO: track which featured snippets and People Also Ask answers you own, and watch Search Console for impressions on question-led queries.
- GEO: run a fixed set of real customer prompts across ChatGPT, Perplexity, Gemini and Google AI Mode on a schedule, and record who gets mentioned and cited. Then add AI referral traffic in Google Analytics 4 (visits from domains like chatgpt.com and perplexity.ai).
AI answers change from one day to the next, so trends over repeated tests tell you far more than any single screenshot. That’s the basis of our AI visibility tracking.