What the three terms mean
SEO is search engine optimisation: getting your pages found, crawled and ranked, so that a shopper who searches clicks through to you.
AEO is answer engine optimisation: writing so that a search engine or assistant can lift a direct answer from your page. Featured snippets, voice answers and Google's AI Overviews are all answers of this kind.
GEO is generative engine optimisation: being cited or named inside an answer that an AI model writes, in ChatGPT, Perplexity, Gemini, Copilot or Google's AI Mode. The name comes from a research paper first posted in November 2023 and presented at the KDD conference in 2024.1
The terms are new enough that people are still looking them up. In the UK, "generative engine optimisation" is searched about 1,100 times a month, "answer engine optimisation" about 800 times and "geo vs seo" about 700 times.8
| Compare | SEO | AEO | GEO |
|---|---|---|---|
| Where you show up | The list of results | The answer above the results | Inside an AI-written answer |
| What you earn | A ranked link | Your words, quoted | A mention or a cited link |
| What a win looks like | A shopper clicks through | The answer points to your page | The AI recommends your brand |
| What moves it | Crawlable pages, relevance, links | Clear questions with short, direct answers | Facts, sources, product data and mentions elsewhere |
| How you measure it | Positions, clicks, orders | Snippets and AI Overviews held | Citations, mentions, referral visits |
How much of this is new
Less than the three names suggest. Google's documentation on its AI features says the same SEO best practices apply to AI Overviews and AI Mode, with no extra requirements, and that a page has to be indexed and eligible for a snippet before it can be used.2 Its newer guide on generative AI features adds that you do not need an llms.txt file, special markup or content broken into chunks, and that Google Search ignores llms.txt altogether.3
Google also describes how these features work. Both can use what it calls query fan-out, where one question is split into several related searches and the answer is built from the results.2 That is a good reason to answer the specific questions inside a topic, and not only the headline one.
The chat assistants add two things that Google does not ask for. The first is access. OpenAI runs a separate crawler for ChatGPT search, and a site that blocks it is left out of search answers.4 The second is what other people say about you. OpenAI says ChatGPT's product results draw on structured product data, on third-party content such as reviews, and on what the model already knows.5
For Google, GEO is SEO done properly. For the chat assistants, add two jobs: let their crawlers in, and earn mentions on pages you do not control.
What the research says works
The paper that named GEO tested ways of rewriting a page against a benchmark of 10,000 queries, and measured how visible the page became in generated answers.1 Four findings are worth knowing.
- The best methods raised visibility by up to 40% on the benchmark, and by up to 37% when the authors tested them on Perplexity.
- Citing sources, adding quotations and adding statistics worked best. Making the writing more fluent and easier to read gave 15 to 30%.
- Keyword stuffing did poorly. The old habit of repeating the phrase does not carry over.
- Lower-ranked pages gained the most. Citing sources lifted the page ranked fifth by 115.1%, while the top-ranked page lost 30.3% of its visibility.
The last finding matters for a challenger brand. A clear, well-sourced page can be picked up by an AI answer without holding first place in the search results.
What an ecommerce brand should do
Five jobs, in the order we do them.
- Keep the foundations in orderIndexable pages, fast templates and a clean collection and product structure. A page Google cannot index cannot appear in an AI Overview either.2
- Make product facts machine-readableComplete product data in your structured data and your Merchant Center feed: price, availability, variants, shipping and returns. Google names Merchant Center feeds as a route into its AI answers,3 and Shopify sends catalogue data to ChatGPT and Microsoft Copilot for eligible stores.6
- Answer the buying questions on the pageSizing, materials, care, comparisons and which product suits whom, each with the direct answer first and the evidence under it. Use real figures and name your sources, because that is what the research rewarded.1
- Earn mentions you do not controlReviews, independent roundups, press and community threads. The assistants read them, and Google says chasing inauthentic mentions is not useful, so the real ones are the only ones worth having.35
- Measure the new surfacesTrack which AI answers cite or name you for your buying questions, watch referral visits from the assistants, and look for the generative AI report in Search Console, which Google announced in June 2026 and is rolling out to a first set of sites.3
None of the five is a separate project. The first three are ecommerce SEO, the fourth is digital PR and the fifth is reporting. That is the practical meaning of Google's guidance: one programme, with the AI surfaces added to what it measures.
What it looks like on a real store
What not to pay for
- An llms.txt file as a service. Google has said its Search ignores the file,3 and Shopify now serves one for its stores automatically.7
- Keyword stuffing dressed up as AI optimisation. It performed poorly in the research.1
- Bought or invented mentions. Google says seeking inauthentic mentions is not useful.3
- Rewriting your site into chunks for AI. Google says there is no need.3
If a proposal for GEO does not start with your product data, your pages and your reviews, it is selling the name and not the work.
Questions
- What is the difference between GEO and SEO?
- SEO earns a ranked link in search results. GEO earns a mention or a citation inside an answer written by an AI model such as ChatGPT, Gemini or Perplexity. Both rest on the same foundations.
- Is GEO replacing SEO?
- No. Google says the same SEO best practices apply to its AI features, and a page has to be indexed before it can appear in an AI Overview. GEO adds jobs to SEO and does not replace it.
- What is AEO?
- Answer engine optimisation: writing so that a search engine or assistant can lift a direct answer from your page, as in featured snippets, voice answers and Google's AI Overviews.
- Do I need an llms.txt file?
- Not for Google, which has said its Search ignores the file. Shopify stores already serve one automatically, so there is nothing to buy.
- How do I measure GEO?
- Track which AI answers cite or name your brand for your buying questions, watch referral visits from the assistants in your analytics, and compare both month by month.
Sources
- 1GEO: Generative Engine OptimizationAggarwal and others. First posted November 2023, presented at KDD 2024.
- 2AI features and your websiteGoogle Search Central.
- 3Optimizing your website for generative AI features on Google SearchGoogle Search Central, added May 2026.
- 4Overview of OpenAI crawlersOpenAI.
- 5Shopping with ChatGPT SearchOpenAI Help Center.
- 6Agentic storefrontsShopify Help Center.
- 7Shopify Catalog and product discovery for agentic storefrontsShopify Help Center.
- 8Ahrefs Keywords ExplorerUK monthly search volumes, read on 10 November 2026.
Drafted with the Rembanx engine on Claude from the sources above, then checked and approved by Matthew Banks. Prices, product features and search volumes were checked on 10 November 2026 and can change.