AEO vs GEO vs AI SEO: what's the difference?

The three terms name overlapping work, and the methods are mostly the same

AEO, GEO and AI SEO all describe one goal: getting a business found and used by systems that answer questions. Each term came from a different moment, and each stresses a different part of the job. Underneath, the work is the same. Pages must be reachable by crawlers, indexed by search engines, and clear about the question they answer.

This guide covers where each term came from and what it stresses. For how AI answers change traditional search work, read our guide to AI SEO vs SEO.

AEO is the older term, and it is built around direct answers

Answer engine optimisation (AEO) is the work of shaping a page so that a search engine or assistant can lift a direct answer from it. An answer engine is any system that replies to a question with an answer, instead of a list of links. The term grew up with featured snippets in Google and with voice assistants, which read out one answer. We have not found a reliable record of who first used it or when.

Featured snippets explain the habits AEO built. Google describes them as results "where the format of a regular search result is reversed", so the answer text shows before the link (Google Search Central). Google's systems decide which pages make good featured snippets, and they show those pages first. You cannot mark a page as a featured snippet. You can only opt out, with the nosnippet or data-nosnippet rules. Google adds that a low max-snippet setting does not guarantee the snippets stop.

So AEO practice settled on question-shaped headings, a short answer in the first sentence or two, and the detail after. Those habits still work, because AI answers quote pages in much the same way. Our answer engine optimisation page covers how we do this work.

GEO comes from a 2023 research paper, and it stresses citations in AI answers

Generative engine optimisation (GEO) is the work of making a page more likely to be used and cited in an answer that an AI model writes. A generative engine is a search system that reads several pages and writes one reply, such as ChatGPT search, Perplexity or Google AI Mode.

The term comes from "GEO: Generative Engine Optimization", by researchers at Princeton University and IIT Delhi. It was first posted on 16 November 2023 and accepted to KDD 2024, a data science conference (arXiv). The authors tested nine ways of rewriting a page. They measured how much of each generated answer drew on that page.

Adding quotations, adding statistics and citing sources did best. The paper's headline result is a visibility gain of up to 40%. Keyword stuffing did worse than leaving the page alone. Lower-ranked pages gained most: citing sources raised the visibility of the fifth-ranked result by 115.1%. The tests ran on a lab benchmark, and the engines are different today. Our generative engine optimisation page covers how we apply it.

AI SEO is the umbrella term, and it includes ordinary SEO

AI SEO is the name for all of this work as one programme, and it is the term we use. It covers AEO, GEO and ordinary search engine optimisation (SEO). Ordinary SEO stays in because AI answers are built on search indexes.

Google says that to appear in AI Overviews or AI Mode, "a page must be indexed and eligible to be shown in Google Search with a snippet". It adds: "There are no additional requirements to appear in AI Overviews or AI Mode" (Google Search Central). Other engines publish similar rules for their own crawlers. OpenAI says sites that opt out of OAI-SearchBot "will not be shown in ChatGPT search answers" (OpenAI).

So any AEO or GEO plan has to start with crawl access and indexing. Our AI SEO services page sets out how we run the full programme.

Side by side, the terms differ in emphasis more than in method

Each term points at a different place where your business can appear. The levers overlap heavily, and each row depends on the one above it.

In practice, AEO and GEO work on different parts of the same page

The differences are real but small. Each one changes how you write a page:

• AEO leans on question-shaped headings and short answers. Each heading covers one question, and the first sentence under it gives the answer.
• GEO leans on citable facts: figures with a source and a date, named sources, and claims that other sites corroborate. Corroboration means other sources say the same thing about you, so an engine does not rely on your word alone.
• Both depend on crawl access and indexing. If a crawler cannot reach a page, neither set of habits counts.

One page can do all three. Our guide to writing pages answer engines quote shows the AEO side in detail. For the GEO side, read what the GEO research found, including its limits.

The name on the service matters less than the checks behind it

The label an agency puts on its service tells you little. One agency sells AEO and another sells GEO, and the work behind both is often the same list. Ask what they will check and change:

• Whether AI search crawlers such as OAI-SearchBot and PerplexityBot can reach your site.
• Whether your key pages are indexed in Google.
• Whether each service page answers its question in its first two sentences.
• Which facts and figures on your pages carry a source.
• How they will measure which AI tools name you over repeated asks, since answers vary.

Be wary of any promise of a featured snippet or an AI mention. Google and the AI companies make those choices, and no agency controls them. Our guide to choosing an AI SEO agency has seven checks to run before you sign.