SEO, GEO, AEO, AIO, SXO: what the real difference is
Five acronyms for a profession that keeps changing. Below: what each one means, which question it answers, where the industry has no consensus and why we still use them separately.
The short answer
All five describe the same ambition — to be found — but at different stages of the journey. SEO gets you into the list of results. GEO gets you into the set of sources an AI engine can cite. AEO makes sure a fragment that really answers the question can be extracted from your page. AIO is either an umbrella term that overlaps GEO and AEO, or shorthand for Google AI Overviews — in which case it names a product, not a discipline. SXO covers what happens after someone has found you.
The distinction missing from most comparisons on the internet, including the table below if you read it in a hurry: SEO, AEO and GEO are practices; ChatGPT, Perplexity, Gemini, Copilot, voice assistants and Google AI Overviews are surfaces. Asking "AEO or AI Overviews?" is like asking "shopping or supermarket?".
The part few people say: there is no standard that separates these terms. In early 2026 there was no established definition in the literature, and practitioners use them interchangeably. Any strict hierarchy you see anywhere — including ours, below — is a working convention, not a fact.
Five-column comparison
| Term | Question it answers | Where it applies | What the work involves | How it is measured |
|---|---|---|---|---|
| SEO Search Engine Optimization | Do I appear in the list of results? | Classic search engines | Technical, content, authority — the whole package | Rankings, organic traffic, impressions |
| GEO Generative Engine Optimization | Am I chosen as a source in the generated answer? | ChatGPT, Perplexity, AI Overviews, Gemini, Copilot | Bot access, brand entity, presence on both channels (retrieval + parametric) | Citations, share of model voice |
| AEO Answer Engine Optimization | Can a fragment be extracted from my page? | Answer engines, snippets, assistants | Passage-level structure, self-contained question→answer, schema | Snippets won, passages cited |
| AIO AI Optimization / AI Overviews | Depends on which meaning — see below | Either an umbrella (chatbots, assistants, agents), or strictly the AI summary in Google | As an umbrella: overlaps almost completely with GEO+AEO. As "AI Overviews": it is a surface, not a discipline — the work for it remains GEO+AEO | No distinct metric of its own (appearing in AI Overviews is measured like any citation) |
| SXO Search Experience Optimization | What happens once it has found me? | The experience after the click | Speed, clarity, path to conversion | Conversion rate, bounce, Core Web Vitals |
The individual terms, with the mechanism behind them: the full glossary →
"It is still SEO" — and why that does not settle the debate
From Google Search's perspective, optimizing for generative search is optimizing for the search experience, so it is still SEO. — paraphrased from Google's documentation on generative AI features, 2026
It is a correct position and worth taking seriously: Google recommends exactly the classic fundamentals — content that is not a commodity, correct indexing, semantic HTML, accessible JavaScript, a good page experience — and explicitly discourages tricks invented for AI, including llms.txt and "special schema for AI", which does not exist.
The nuance the statement does not cover: Google is talking about Google. Perplexity, ChatGPT Search or Claude have other bots, other access rules and another way of choosing sources. And the parametric channel — what a model "knows" from its training data, independent of any search — has no equivalent in classic SEO. Separate terms are useful for naming these operational differences; they are not useful for selling as a new product work we were already doing.
Why we still separate GEO from AEO
Because they are two different jobs, usually done in a different order, on different timelines.
GEO — the selection problem
Are you in the set of sources the engine can use? It comes down to bot access, your coherence as an entity, and presence in sources the models learned from. Effect on retrieval: days. Effect on parametric: months.
AEO — the extraction problem
Once the engine reaches your page, does it find a fragment it can take as is? It comes down to structure: a descriptive heading, a complete answer in 2-4 sentences, no dependence on context. It can be checked immediately, at passage level.
You can be selected and not citable (the engine opens your page, finds no clean fragment, moves on). You can be citable and not selected (perfectly structured content on a site the bots never reach). That is why we treat them separately — not because a standard obliges us to.
About the terminology
The terms matter less than the result.
A 15-minute discovery call: I will tell you what exactly from the list above is missing on your site — and in what order it would be fixed.