AEO, GEO and AIO: What the Acronyms Mean and Which One You Should Optimise For
Three acronyms, one panic. AEO, GEO and AIO are not competing methodologies — they describe three different jobs. Here is what each one means and the order to work on them.
AEO (Answer Engine Optimisation), GEO (Generative Engine Optimisation) and AIO (AI Optimisation) are not three competing methodologies. They describe three different jobs: being the extracted answer, being the cited source inside a generated response, and being legible to AI systems at all. Most sites need all three, in that order of difficulty and reverse order of effort.
Every few months a new acronym arrives and a wave of posts declares SEO dead. This one is different only in that the underlying behaviour genuinely changed. In the US, 68.01% of Google searches ended without a click across January to April 2026, up from 60.45% in 2024 — SparkToro’s analysis of Similarweb clickstream panel data. And in a Pew Research Center study of 900 US adults who shared their browsing activity in March 2025, users clicked a search result in 8% of visits where an AI summary appeared, against 15% of visits where it did not — while clicking a source link inside the summary itself just 1% of the time (Pew Research Center, published July 2025).
So the acronyms are pointing at something real. They are just badly named. Here is what each one is actually describing.
What is AEO (Answer Engine Optimisation)?
AEO is optimising a page so a machine can lift a complete, correct answer out of it without needing the rest of the page. It is the oldest of the three — it predates generative AI and grew out of featured snippets, voice assistants and People Also Ask boxes.
The unit of AEO is not the page. It is the passage.
An answer engine is looking for a chunk of text that resolves a question standalone. If your definition of a term only makes sense after two paragraphs of preamble, it is a poor extraction candidate no matter how well the page ranks.
What AEO work looks like in practice:
- Headings phrased as the questions customers actually ask, not internal category names
- A 40–60 word direct answer immediately under each heading, before the explanation
- Sections of roughly 150–300 words that each fully answer one thing
- Lists and tables for anything enumerable, because prose is harder to chunk cleanly
- FAQ blocks with genuine questions, marked up with
FAQPageschema and visible on the page
AEO is the highest-leverage and lowest-cost of the three. It is mostly editing. For the page-level mechanics — which passages actually get lifted, and how to write them — see how to get your brand cited by ChatGPT, Perplexity and AI Overviews.
What is GEO (Generative Engine Optimisation)?
GEO is optimising for whether a generative system chooses your page as a source when it composes an answer — and whether it describes you accurately when it does. The term comes from a 2024 KDD research paper by researchers at Princeton University and IIT Delhi, who tested nine content changes against a generative search engine and measured how much each one increased a source’s visibility in the generated answer.
Their finding, simplified: the changes that moved the needle were about credibility, not keywords.
| Change tested | Reported visibility improvement |
|---|---|
| Adding relevant quotations | +41% |
| Adding relevant statistics | +30% |
| Citing credible sources | +30% |
| Improving fluency, clarity and authoritative tone | Smaller but positive |
| Keyword stuffing | No improvement — it performed below the baseline |
(Figures are the paper’s Position-Adjusted Word Count metric, measured on a generative search engine. Treat them as directional rather than as a forecast for your site.)
That last row is the one worth pinning to a wall. In classic SEO, keyword stuffing is merely ineffective. In generative retrieval it made the tested pages less visible than leaving them alone.
The practical translation: GEO is won by publishing things that cannot be synthesised from the rest of the internet. Original data from your own accounts. A documented method with its trade-offs. A specific number and the conditions that produced it. If your article restates what a hundred others say, a model has no reason to credit you over any of them — it already knows the generic version.
What is AIO (AI Optimisation)?
AIO is the broadest of the three: making your business legible to AI systems everywhere they encounter it — crawlers, retrieval indexes, agents and knowledge graphs — not just in a search box. Where AEO is about the passage and GEO is about the source choice, AIO is about the plumbing.
Some people use AIO to mean “AI Overview optimisation” specifically. That narrower reading is common enough to cause confusion, so it is worth defining the term when you use it.
The plumbing layer includes:
- Crawler access. GPTBot, ChatGPT-User, PerplexityBot, ClaudeBot and Google-Extended each need to be permitted in
robots.txt. Blocking a bot does not make you neutral; it makes you uncitable on that platform. - Server-rendered content. If the main text only appears after JavaScript executes, assume some retrieval systems never see it.
- Entity clarity.
Organizationschema, consistent naming, and links to the profiles you control, so a model connects the page to a known company rather than an anonymous domain. - Machine-readable summaries. An
/llms.txtfile at your root describing what the site covers. Not a ranking factor, not officially supported by Google, and roughly an hour of work — worth doing on that basis alone. - A public, parseable pricing or services page. Agents evaluating vendors on a buyer’s behalf skip what they cannot read. “Contact sales” behind a form is invisible to them.
How the three fit together
Think of it as a funnel with three gates.
| Gate | The question being answered | Discipline | Effort |
|---|---|---|---|
| 1. Legible | Can the system access and parse this at all? | AIO | Low, one-off |
| 2. Extractable | Is there a clean passage that answers the query? | AEO | Medium, per page |
| 3. Citable | Is there a reason to credit this source? | GEO | High, ongoing |
You cannot skip forward. Original research on a page that GPTBot is blocked from is invisible. Covering a whole subject so retrieval systems find you across related questions is a separate job again — that is what topic clusters are for. A perfectly structured page that says nothing only anyone else has said gets read and discarded.
Does any of this replace SEO?
No — and the framing is the mistake.
Google’s own guidance is that its generative features run on the same core ranking and quality systems as the rest of Search, and that no special markup or AI-specific files are required to appear in them. Their advice is unchanged: write helpful content for people, organise it with normal headings, and do not produce separate versions aimed at machines. Producing AI-targeted content variants risks being treated as scaled content abuse.
The other engines behave differently. ChatGPT, Claude and Perplexity draw from a wider pool than Google’s top-ranked results, reward extractable structure more visibly, and cite third-party sources — forums, review sites, reference works — far more heavily than most brands expect.
The resolution is less complicated than the discourse: strong traditional SEO remains the foundation, structural clarity is the layer you add on top, and neither requires writing for a machine at the expense of a reader. Everything in this article is also just good technical writing.
Which should you work on first?
In order, and each one is a week of work at most for a typical site:
- Unblock the crawlers. Check
robots.txtfor the five bots listed above. This takes ten minutes and gates everything else. - Rewrite your ten highest-intent pages answer-first. Take each section, put the conclusion in the first two sentences, then explain. Read each section in isolation — if it needs the paragraph above it to make sense, it is not done.
- Turn category headings into customer questions. “Channel considerations” becomes “How much does cost per acquisition vary by channel?”
- Add
FAQPageandArticleschema to pages that already contain visible questions, answers, an author and a modified date. - Publish one piece containing data only you have. A quarter of your own numbers, aggregated. This is the part competitors cannot copy in an afternoon.
Frequently asked questions
Is AEO the same as SEO?
No. SEO optimises for ranking a page in a list of results. AEO optimises for a passage being extracted as the answer, which can happen whether the page ranks first or twentieth. The techniques overlap heavily, but the target is different.
Is GEO just a rebranded version of AEO?
They are distinct. AEO concerns whether a usable answer can be pulled from your page. GEO concerns whether a generative system chooses your page over the alternatives when it assembles a response — a judgement about credibility, originality and evidence rather than structure.
Do I need an llms.txt file?
It is optional. No major engine has confirmed it as a ranking signal and Google has said no AI-specific files are required. It is cheap to produce and makes your site easier to summarise correctly, which is reason enough for most teams.
How do I know whether any of this is working?
Rank tracking will not show it. Run your twenty most important customer questions through ChatGPT, Perplexity, Gemini and Google’s AI Overviews once a month and record who gets cited. Then watch referral traffic from AI hosts in analytics, and watch Search Console for pages gaining impressions while clicks stay flat — that pattern usually means you are being surfaced and answered above the fold.
Can I optimise for AI search without an existing SEO foundation?
Partly. Structure and originality can earn citations from ChatGPT and Perplexity on a modest domain. Google’s AI Overviews correlate strongly with conventional rankings, so a weak organic position limits you there regardless of how well the page is written.
ThynqAi builds SEO and organic growth systems for teams that need to be found by both people and machines. If you want to see how your site currently reads to an AI assistant, ask us for an audit.
