AEO vs SEO vs GEO: what each one is, and which your business needs

What is the difference between AEO and SEO?

You may have been told your business needs AEO now, on top of SEO or instead of it. The two share most of their work. They differ in where the result shows and how you tell that it worked:

• SEO, search engine optimization: the work that gets your pages crawled, indexed and ranked in search results. Success is a ranking, a click and then an inquiry.
• AEO, answer engine optimization: the same work aimed at tools that reply with an answer instead of a list of links, such as Google’s AI Overviews and AI Mode, ChatGPT search and Perplexity. Success is your page quoted or linked in that answer.
• What they share: Google says its AI features depend on its core ranking systems and the systems that block spam, and a page has to be indexed and eligible to show with a snippet before they can use it (July 2026).

Take a question like “how long does a website redesign take”. SEO aims for your page to rank in the results below Google’s AI Overview. AEO aims for the Overview itself, or ChatGPT’s reply to the same question, to quote your page.

Google’s guide to hiring search help lists work for generative AI among the useful services an SEO can offer, and suggests checking that any AEO or GEO advice lines up with Google’s official guidance (June 2026). That’s the test to apply to anyone who sells you either.

How is generative engine optimization different from traditional SEO?

The name GEO comes from a research paper, “GEO: Generative Engine Optimization”, by Pranjal Aggarwal and colleagues, first posted in November 2023 and accepted to the KDD 2024 conference. It defined GEO as helping content creators raise their content’s visibility in the answers that generative engines write. Three things change when an answer replaces a list of results:

• One answer draws on several sources: in Pew Research Center’s study of Google searches made in March 2025, 88% of AI summaries cited three or more sources, and 1% cited a single one.
• The question gets broken up: Google’s AI Overviews and AI Mode may run several related searches across subtopics before they answer, which Google calls query fan-out (December 2025), and its systems understand synonyms and meaning, so a page needn’t repeat every phrasing (July 2026).
• Fewer clicks reach the site: in the same Pew study, people clicked a traditional result on 8% of visits that showed an AI summary, against 15% of visits without one, and clicked a link inside the summary on 1% of visits. Visits with a summary also ended the browsing session more often: 26%, against 16%.

The same pages serve both. What changes is how you judge them: by whether AI answers use them, as well as by rankings and clicks.

How do SEO, AEO and GEO compare side by side?

Side by side, the three differ mostly in where the result appears and how you measure it.

Does AEO replace SEO?

No. For Google, AEO depends on SEO. Google says a page needs nothing extra to appear in AI Overviews or AI Mode: it has to be indexed and eligible to show with a snippet, and no special technical work is required (December 2025). Since August 31, 2026, every site also has a Search generative AI control in Search Console. It is set to include by default, and a site switched to exclude drops out of AI Overviews, AI Mode and the AI features in Discover. Meeting those conditions still doesn’t mean a page will be shown, and a page that isn’t indexed can’t appear in Google’s AI answers at all. Google also says you don’t need new machine-readable files, AI text files or special schema.org markup for its AI features.

ChatGPT search works from a crawler of its own. OpenAI says OAI-SearchBot is what surfaces sites in ChatGPT’s search answers, and a site that blocks it won’t be shown in those answers, though it can still appear as a navigational link.

So AEO adds a layer on top of SEO: answers written for the questions buyers ask, and the measuring of AI answers. The pages, the crawling and the indexing underneath stay the same work.

How does generative engine optimization work?

Google’s July 2026 guide names two techniques behind its AI answers. In retrieval-augmented generation, also called grounding, its systems retrieve pages from Google’s index and base the answer on them. In query fan-out, the model generates several related searches at once, to fetch more results for the question. Each technique points to part of the work:

• Be retrievable: an answer can only use a page that crawlers can reach and that is indexed, so robots.txt rules and CDN settings that block crawlers come first.
• Be the clearest source: a plain answer near the top of the page, in text, gives the system something it can use.
• Cover the questions around the main one: fan-out searches the related questions too, though Google warns that making pages for every variation of a query to manipulate rankings breaks its scaled content abuse policy (July 2026).
• Keep facts consistent: the same name, services and details on your pages, in your structured data and on your Business Profile.

Crawler settings matter beyond Google. For Google, Googlebot’s robots.txt rules are the control for Search, and a separate token, Google-Extended, limits the use of your content for training and grounding in some other Google systems (December 2025). At OpenAI, OAI-SearchBot crawls for ChatGPT search and GPTBot crawls for training, and each setting is independent.

The 2023 paper tested changes to page content on its own benchmark of queries and reported visibility gains of up to 40% in generative engine responses, with results that varied by subject area (Aggarwal and others, 2024). It was measured on one benchmark in a lab setting, so it says little about how any one site will fare.

How often do AI answers appear in search?

It depends on the question, and on who is searching:

• Pew Research Center, March 2025: 58% of the 900 US adults in the study saw at least one AI summary, and 18% of their 68,879 Google searches produced one. Searches phrased as questions produced one 60% of the time, and searches of ten words or more did 53% of the time, against 8% for searches of one or two words.
• Our own check, October 30, 2026: Google showed an AI Overview for 131 of 155 head terms for web design, SEO, GEO, software and AI services (Ahrefs, US data), including 28 of 30 SEO terms and 15 of 17 GEO terms.
• Which pages get cited: in the same research, 46 of 62 buyer keywords showed AI Overview citations, 407 in all. Explainers drew 25.1% of them, videos 18.9%, service pages 13.0%, cost guides 10.6% and best-of lists 8.8%, and YouTube alone took 17.9%. Sixteen keywords had none, among them “local seo services” and “how much does seo cost”.

Two cautions. Pew counted all kinds of everyday searches, while ours covers commercial head terms and Google’s AI Overviews only, not ChatGPT, Perplexity or Gemini. And AI Overviews show only when Google judges they add something, so they often don’t appear (December 2025).

Can you measure AI visibility, and how well?

Partly. Each source shows a part of the picture:

• Search Console: Google counts appearances in its AI features in the Performance report under the Web search type (December 2025), and its July 2026 guide points to a Generative AI performance report. Both cover Google only.
• Analytics: Google suggests tracking conversions and time on site in a tool such as Google Analytics, to see what visits from its AI features do once they arrive (December 2025).
• Third-party trackers: Google says no third-party tool has access to its internal ranking or AI systems, and warns against tools that promise ranking success (July 2026). A tracker sees the answers it asked for, on the day it asked.
• A fixed set of questions: the same buyer questions, run each month in each tool and scored as an appearance rate, the share of answers that name the business. It shows direction, and it can’t give a position the way a rankings report does. The questions stay fixed so the months compare: change the questions and the rate changes with them.

Answers also move. Google says AI Mode and AI Overviews may use different models and techniques, so their responses differ (December 2025), and Pew notes that a summary may change over time (July 2025). Any single snapshot is one day’s answer. We measure AI visibility the fixed-question way, as appearance rates, and we never promise a citation.

What doesn’t help, according to Google?

Google’s July 2026 guide lists tactics you can set aside for Google Search:

• llms.txt and other AI files: Google Search doesn’t use llms.txt, so the file neither helps nor harms there, and keeping one for other services is fine.
• Splitting pages into small chunks: pages don’t need to be cut into pieces for AI to use them.
• Rewriting just for AI: Google’s systems understand synonyms and meaning, so there’s no need to rewrite pages for machines.
• Seeking mentions that aren’t genuine: it isn’t as helpful as it may seem, since Google’s AI features rest on the same ranking and spam systems as the rest of Search.
• Special markup: structured data isn’t required for AI features and there is no special schema for them, though it still helps pages qualify for rich results.

We add an llms.txt file to the sites we build, for the other services that may read one. For Google Search, it makes no difference.

What should you do first?

Which do you need? For Google, AEO and GEO build on SEO, so most businesses need one piece of work done in order, with each step resting on the one before:

1. Make sure you can be crawled and indexed: check that robots.txt and your CDN let search crawlers in, and that your key pages are indexed in Search Console.
2. Decide on AI access on purpose: OAI-SearchBot, GPTBot and Google-Extended are separate robots.txt settings, so choose for each one. Blocking OAI-SearchBot keeps your pages out of ChatGPT’s search answers, and blocking GPTBot tells OpenAI not to use them to train its models. In Search Console, check that the Search generative AI control is set to include, its default, unless you want the site kept out of Google’s AI features.
3. Answer buyers’ questions in text, near the top: write the plain answer first, in the words buyers use, then the detail.
4. Keep your facts the same everywhere: your name, services and details should match on your site, in your structured data and on your Business Profile.
5. Publish pages that explain, price and compare: in our October 2026 research these drew about 45% of AI Overview citations, and Google asks for content with a view of its own, beyond what everyone already says.
6. Measure what you can trust, and be wary of promises: check any AEO or GEO advice against Google’s own guidance. In Google’s words: “No one can guarantee a #1 ranking on Google.” The same holds for AI answers.

Steps 1, 2 and 4 are settings you check once and revisit when the site changes. Steps 3, 5 and 6 are the ongoing work.

If you’d rather have this done for you, our GEO work makes a business easier for AI answers to find, read and cite, adds monthly tracking of mentions in AI answers to SEO, and reports them as appearance rates, never as a promise. The answer engine side is on our answer engine optimization page, and it all starts with a 15-minute call.