Guide · September 2026
What are SEO, AEO, GEO and AIO?
Four acronyms, one job: being visible where your customers actually look. SEO gets you found in search results, AEO gets your content lifted out as the answer, GEO gets you mentioned in AI-generated answers, and AIO is the umbrella over it all. This guide explains each one — what it is, how to do it, and why it matters.
First, a small confession: the industry has produced more alphabet soup than the field deserves. The terms overlap, get used interchangeably, and new ones arrive every year. But underneath the acronyms sits something real: the way people find products is changing. They still search — and increasingly they also ask ChatGPT, Claude, Gemini or Perplexity, or get an AI summary at the top of their search results.
Each acronym names optimization for one of those surfaces. You don’t need four projects and four agencies. You need to know what’s what, and where the effort actually pays off. Let’s take them one at a time.
What is SEO — search engine optimization?
SEO (Search Engine Optimization) is the work of making your website visible in search engine results when customers search for what you offer.
SEO is the oldest of the four disciplines — it has been around since the 1990s — and it stands on three legs: technology (can crawlers read and understand your site?), content (do your pages answer what people actually search for?) and authority (links and mentions from other sites that signal you can be trusted).
How do you do it?
- Make the site readable: let search crawlers in, provide a sitemap, and keep pages reasonably fast on mobile.
- Write content that matches search intent — pages should answer what the customer is wondering, not just describe you.
- Use structured data (schema.org) so machines understand what is a product, a price, a business.
- Build authority over time: links and mentions from sites people trust.
Why does it matter?
Search is still the biggest discovery channel, and everything else builds on the SEO foundation. AI systems read the web through the same kind of crawlers — a site search engines can’t read is usually one AI can’t read either.
What is AEO — answer engine optimization?
AEO (Answer Engine Optimization) is shaping your content so answer engines — AI summaries in search, voice assistants and chatbots — can lift your answer out directly.
An answer engine doesn’t show ten blue links; it answers. Google’s AI Overviews, featured snippets and voice assistants pull a passage from a page and present it as the answer. AEO is about being that passage.
How do you do it?
- Phrase headings as the questions customers actually ask.
- Answer in the first sentence under the heading, then elaborate — not the other way around.
- Write short, self-contained paragraphs that make sense lifted out of the page.
- Add an FAQ section with FAQPage schema, and use concrete facts and numbers instead of marketing language.
Why does it matter?
When we surveyed 99 Norwegian online stores in August 2026, 55% of buyer questions triggered an AI summary in Google — but only 37% of those summaries cited the store the question was about. Meanwhile just 15% of the stores used question-shaped headings, and not one of 78 had FAQ schema. The work is cheap, it’s fast — and almost nobody has done it.
What is GEO — generative engine optimization?
GEO (Generative Engine Optimization) is making sure generative engines like ChatGPT, Claude, Gemini and Perplexity mention and cite your brand when they write their answers.
The term comes from a 2023 research paper, and it points at something important: a generated answer is written from many sources — including what others have written about you. The models lean on entities and coverage: Wikidata, reviews, comparisons, industry press and forums. GEO therefore widens the view from your own website to your whole footprint.
How do you do it?
- Make the brand unambiguous to machines: a complete Wikidata entity and consistent descriptions everywhere.
- Earn independent coverage in the sources models read: industry press, product reviews, directories and comparisons.
- Make your own content citable: concrete numbers, sources, and claims someone can quote verbatim.
- Be the obvious answer to something: a sharp profile gives you questions where the AI has no reason to pick anyone else.
Why does it matter?
This is where recommendations are won. In our survey, domain authority barely correlated with AI citation at all (r = 0.05) — the winners were the stores with a clear profile and content shaped as answers, not the ones with the best technical scores. Technology decides whether you’re in the game; relevance and reputation decide whether you get picked.
What is AIO — AI optimization?
AIO (AI Optimization) is the umbrella term: making your whole brand — content, data and systems — readable and usable for AI systems.
AIO is the youngest and loosest of the terms, so keep your guard up: some use it as a synonym for GEO or AEO, others for optimizing specifically toward Google’s AI Overviews. The most useful reading is the umbrella — plus the machine side: getting ready for AI agents that don’t just answer, but act on the user’s behalf.
How do you do it?
- Put structured data on everything: organization, products, prices, availability.
- Offer machine-readable entry points where they make sense: feeds, open APIs and an llms.txt file.
- Decide consciously which AI crawlers may read your site — blocking everything also means becoming invisible.
- Keep an eye on the emerging agent standards; the field moves fast.
Why does it matter?
AI assistants are turning into agents that compare and order on the user’s behalf, and that requires systems machines can read. But be honest about the order of operations: in our survey, the one store with full agent infrastructure went uncited in every AI summary we measured it in. Advanced machinery doesn’t buy you visibility today — it gets you ready for the channel that’s coming.
How do the four fit together?
It’s easiest to see side by side:
| Term | Engine | You optimize | The goal |
|---|---|---|---|
| SEO | Search engines (Google, Bing) | Technology, content and links | Rank in the search results |
| AEO | Answer engines (AI summaries, voice, snippets) | Content form: questions and answers | Get lifted out as the answer |
| GEO | Generative engines (ChatGPT, Claude, Gemini, Perplexity) | Entities, coverage and citability — beyond your own site | Get mentioned and cited in generated answers |
| AIO | AI systems broadly, including agents | Machine readability: data, feeds, protocols | Be readable — and usable — by AI |
Notice what they share: it’s the same website, the same content and the same reputation underneath all four. This isn’t four projects — it’s one discipline with four surfaces. And the division of labour is clear: the technical work is the floor — it decides whether you’re in the game at all. Relevance, content form and independent coverage decide whether you win.
If you want the numbers behind that claim, they’re in our survey of 99 Norwegian online stores (in Norwegian).
Where should you start?
The order below is the one we believe pays best — and it’s quite different from buying a little of everything:
- Get the technical floor in place (SEO). Crawlability, indexing and basic structured data. Don’t spend months polishing what already works.
- Be the obvious answer to something. Sharpen your profile. The more clearly you can say what you alone offer, the more questions exist where the AI has no reason to pick anyone else.
- Shape your content as answers (AEO). Question headings, answer first, short paragraphs, FAQ schema. This can change in days, and almost nobody has done it.
- Earn independent coverage (GEO). Industry press, reviews, comparisons. This takes the longest, so start early — but don’t let it block step 3.
- Make the brand unambiguous to machines (AIO). A complete Wikidata entity, consistent data, a deliberate stance on AI crawlers. Hours, not months — once the coverage exists.
Note the order: content form before reputation, and both before more technical polish.
Frequently asked questions
Are AEO and GEO the same thing?
No, but they overlap. AEO is about the form of your own content — whether a paragraph can be lifted out as a finished answer. GEO is about being mentioned and cited in AI-generated answers, and pulls in sources beyond your site: entities, coverage and reviews. In practice the terms get used interchangeably, so always ask what is actually being measured.
Do AEO and GEO replace traditional SEO?
No. AI systems read the web through the same kind of crawlers search engines use, and a site that is invisible in search is usually invisible to AI too. SEO is the foundation; AEO and GEO build on top of it. You add — you don’t swap.
How much do technical scores matter for AI visibility?
Less than they’re often sold as. In our survey of 99 online stores, the overall technical score explained about 4% of the differences in AI citation (r = 0.20), and domain authority explained practically nothing (r = 0.05). The technical work is the floor you stand on — the difference is made by relevance, content form and coverage.
Why can’t I just use a free AEO checker?
You should! Free checkers are useful for weeding out the obvious gaps, like a missing sitemap or absent structured data. But thorough, complicated assessments are something they necessarily can’t offer: both the heavier analyses themselves and the data sources behind them — search data, authority, media coverage — are third-party tools that cost money. So start free, and get a full report when you want the whole picture. An Online Visibility Report catches the obvious gaps too, of course — along with everything the free tools can’t see.
How do I find out whether AI assistants mention my brand?
Ask them. Pose your customers’ own buying questions — without your brand name — to ChatGPT, Claude and Gemini, and note whether you’re mentioned, and who is mentioned instead. You can do that by hand for a handful of questions; an Online Visibility Report does it systematically across assistants and regions, and audits your website in the same pass.
Closing thoughts
Four acronyms, one discipline: being worth mentioning, and easy to cite. Don’t let the alphabet soup panic you into buying “AI optimization” off the shelf. Finish the floor, sharpen the profile, shape the content as answers, and build coverage over time.
The terms will change again — they did last year too. The fundamentals won’t: honest content that answers real questions, from a brand that can be trusted. Good luck!