GEO vs AEO vs LLMO: the AI-search alphabet soup, explained
GEO, AEO, LLMO, AIO and GSO are, in practice, different names for the same goal: getting your brand named and cited when AI engines answer a question. The industry hasn't settled on one term, and the distinctions between them are mostly emphasis, not method. If you're choosing what to actually do, the label matters far less than the fundamentals - crawlability, entity clarity, answer-shaped content, and corroboration.
What each term means
- AEO - Answer Engine Optimization. Structuring content so it gets extracted and surfaced as a direct answer. Originally associated with voice search and featured snippets; now used broadly for AI answers.
- GEO - Generative Engine Optimization. Optimizing your content and digital presence so generative engines (ChatGPT, Perplexity, Gemini, Google AI Overviews, Claude) cite, mention or recommend you.
- LLMO - Large Language Model Optimization. Same goal, framed around the underlying models rather than the search interface.
- AIO / GSO / "AI SEO". Further variants - AI Optimization, Generative Search Optimization - that different practitioners prefer for the same work.
Curious how AI engines describe your brand right now? Get a free visibility audit and see where you stand across ChatGPT, Gemini and Perplexity.
Do the differences actually matter?
Mostly no. Surveys of the field in 2026 found practitioners using these acronyms interchangeably, with few maintaining one consistent term across a year. The clearest distinction anyone draws is the old one between this whole family of terms and traditional SEO: SEO is about ranking pages for clicks; this family is about being selected as a source in a synthesized answer. Beyond that, arguing GEO-versus-AEO is mostly semantics.
Google's own position is blunter still: from its perspective, optimizing for its generative features is just optimizing for search - i.e. still SEO - and it cautions against treating "AEO/GEO hacks" as a separate discipline. That's a useful reminder not to chase tricks. But the buyer behaviour the terms describe - people getting answers from AI instead of clicking links - is very real, whatever you call the response to it.
What to focus on instead of the label
Whichever acronym your agency uses, the work that moves the needle is the same:
- Be crawlable by AI bots - the most common silent failure.
- Be a clear entity - consistent facts, structured data, and a
sameAstying your profiles together. - Write answer-shaped content that leads with the answer.
- Earn corroboration from the third-party sources models trust.
- Measure citations, not just rankings, and maintain them over time.
If you're new to the category, our primer on what AEO is and the breakdown of how AEO differs from SEO are the right next reads.
See how AI describes you today
Stellarcast monitors whether your brand is named and cited across ChatGPT, Claude, Perplexity, Gemini and Copilot, diagnoses why competitors win the prompts you don't, helps you fix it, then proves the lift. Request a free audit and see exactly where you stand.
Get your free visibility audit"A team with a mediocre acronym and a running loop will beat a team with the perfect acronym and a one-time audit every single time."
Where each term actually came from
The labels feel interchangeable now, but they didn't arrive together, and knowing the origin tells you why they carry different flavours.
AEO is the oldest. "Answer Engine Optimization" comes out of the featured-snippet and voice-search era, back when winning meant grabbing "position zero" in Google's answer box or being the response Alexa read aloud. There's no single documented person who coined it - it grew inside the SEO community as answer boxes became a thing people optimized for. That heritage is why AEO still carries a whiff of on-page structure and schema markup: it was born optimizing for extraction, not generation.
GEO has a birth certificate. The term "Generative Engine Optimization" was named in a research paper - "GEO: Generative Engine Optimization" by Pranjal Aggarwal and colleagues at Princeton and IIT Delhi, posted to arXiv in November 2023 and later presented at KDD 2024. The paper defined a measurement framework and ran controlled experiments on content strategies for AI answers. That academic origin is why GEO tends to be the term people reach for when they mean generative engines specifically - ChatGPT, Perplexity, Gemini - rather than classic answer boxes.
LLMO and the rest are community coinages. "Large Language Model Optimization," plus AIO, GSO and "AI SEO," showed up organically as agencies and practitioners each tried to plant a flag. None has a founding paper. They're branding as much as terminology.
So the honest lineage is: AEO from search marketing, GEO from research, LLMO from the market trying to name the thing. Same destination, three different roads in.
Where they genuinely differ - and where they fully overlap
If you strip away the marketing, there are two real axes of difference, and everything else is overlap.
Axis one: what surface you picture. AEO leans toward the answer as an artifact - the snippet, the boxed response, the extracted paragraph. GEO leans toward the model doing the generating and the synthesis behind the answer. LLMO leans furthest toward the model itself and how it was trained. In practice these are different camera angles on one pipeline, not different pipelines.
Axis two: how much you emphasize corroboration versus structure. GEO literature puts heavy weight on being cited and corroborated across the sources a model trusts. AEO's older instincts put more weight on clean structure, direct answers and markup on your own page. Both matter, but the emphasis differs by heritage.
Now the overlap, which is most of it. All three want you crawlable by AI bots. All three want a clear, consistent entity. All three want content that leads with the answer. All three want third-party corroboration. And all three measure success the same way - are you named and cited in the response, not just ranked on a page. When a GEO checklist and an AEO checklist sit side by side, roughly 80% of the line items are identical wording. The divergence lives in the framing paragraph at the top, not in the work.
Which term to use with which audience
Since the practice is shared, the smart move is to match the label to the room instead of arguing for a favourite. A quick guide:
- Talking to a research or data-science audience? Use GEO. It has the paper behind it, and people who read arXiv will recognize the provenance and take you seriously.
- Talking to a classic SEO team or agency? AEO travels best. It connects to the featured-snippet work they already know, so it feels like an extension rather than a rebrand they have to relearn.
- Talking to executives or a board? Skip the acronym war entirely. Say "AI search visibility" or "getting cited when AI answers." Leaders care about whether the brand shows up when a buyer asks ChatGPT, not which three letters you filed it under.
- Talking to engineers or a platform team? LLMO sometimes lands better because it foregrounds the model, but be ready to define it - it's the least standardized of the set.
- Writing for search discovery? Use whichever term your actual audience searches for, and mention the others once so the page is findable across all of them. That's optimization, not indecision.
The tell of someone who actually does this work is that they'll switch terms mid-conversation without flinching, because they know the words are pointing at the same thing.
Why the label matters less than the operating loop
Here's the deeper reason the acronym debate is a distraction: none of these terms describes an ongoing practice. They all name an outcome - being cited - without naming how you keep being cited as models retrain and answers shift week to week.
The thing that actually separates teams that win from teams that don't is whether they run a loop, not which label they printed on the deck. A working loop looks like this:
- Monitor. Track how often and where you're named across the engines that matter to your buyers, for the prompts they actually type.
- Diagnose. When you're missing from an answer, find out why - a crawl block, a fuzzy entity, thin corroboration, or a competitor better positioned as the trusted source.
- Execute. Fix the specific gap. Open the bot to the crawler, tighten the entity, publish the answer-shaped page, earn the citation.
- Prove. Re-measure and show the citation appeared or improved, so the work is defensible and repeatable.
Call that loop GEO, AEO, LLMO or nothing at all - the model does not read your label. It reads your page, your entity signals and the sources that corroborate you. A team with a mediocre acronym and a running loop will beat a team with the perfect acronym and a one-time audit every single time. Pick the word that helps your audience understand you, then spend the rest of your energy on the loop.
Frequently asked questions
Is there a difference between GEO and AEO?
In practice, very little. Both describe getting your brand cited in AI-generated answers. AEO leans on the "answer extraction" framing and GEO on the "generative engine" framing, but practitioners use them interchangeably and the underlying tactics are the same.
What does LLMO mean?
Large Language Model Optimization - the same goal as GEO/AEO, framed around the underlying language models rather than the search interface. It's another label for optimizing to be cited by AI.
Which term should I use?
Whichever your team and partners understand. The label has no effect on results; the fundamentals - crawlability, entity clarity, answer-shaped content, corroboration, and measurement - are what matter.
Does Google recognize AEO and GEO?
Google acknowledges the terms but treats optimizing for its generative features as part of normal SEO, and warns against treating "hacks" as a separate discipline. The buyer shift toward AI answers is real regardless of terminology.