SEO · September 4, 2026
AEO vs SEO vs GEO: What Actually Changed
SEO competes for the click. Answer engines compete for inclusion. Here is the difference, with the evidence — including the part most firms selling this will not tell you.
Three acronyms are being sold hard right now, often by people who cannot define them. Here they are in one sentence each.
SEO — search engine optimization. Getting your pages to rank in a list of links.
AEO — answer engine optimization. Getting your content selected for the answer that resolves the query before anyone clicks: AI Overviews, featured snippets, voice results (Semrush).
GEO — generative engine optimization. Structuring your content and presence so generative systems retrieve, summarize, and cite you accurately across ChatGPT, Gemini, Claude, Perplexity, and AI Overviews. The term comes from a 2023 paper by Aggarwal and colleagues, presented at ACM SIGKDD in 2024 (arXiv).
The three overlap heavily and the terminology is not settled. GEO is also called AIO and AI search optimization, and plenty of practitioners use AEO and GEO interchangeably. Arguing about the labels is a waste of a meeting. What matters is what changed underneath them.
Three things genuinely changed
The prize moved from the click to the mention
Under SEO, position one was the goal because position one got the traffic. Under answer engines, the machine returns two to five options and that is the decision. If you are not among them, your reputation, your reviews, and your thirty-year history are not part of the evaluation — because the evaluation happened before anyone reached a website.
The unit of optimization shrank from the page to the passage
SEO optimizes a page. Answer engines lift a passage — a self-contained block of text that answers one question completely enough to be extracted and attributed. Which produces a strange outcome: a page that is excellent as a whole, but contains no cleanly extractable answer, can rank well and never be cited.
Machine-readability replaced keyword density as the binding constraint
Information trapped in PDFs. Offers living inside image flyers. Service lines described only in a video. Specifications that exist as a downloadable document and nowhere else. To a retrieval system, none of that exists.
In our own assessments, the most common cause of invisibility is not weak content. It is good content in an unreadable container.
What the numbers say
Zero-click is now the majority case. 68.01% of US Google searches ended without a click in the first four months of 2026, up from 60.45% in 2024 and 49% in 2019 (SparkToro, covered by Search Engine Land).
Ranking no longer means what it did. Where an AI Overview appears, click-through to the top organic result falls by 58% — measured across 300,000 keywords against December 2025 Search Console data. The same study found 34.5% in April 2025, so the effect is deepening (Ahrefs).
Local is harder still. Analysis of AI local visibility found assistants recommending only 1% to 11% of locations that perform well in conventional local search (Search Engine Land). If you operate in several markets, your visibility is not one number. It is one number per city, and they diverge sharply.
The traffic that does arrive is better. Visitors arriving from AI search convert at roughly 4.4 times the rate of conventional organic (Semrush). Less traffic, more qualified — because the machine already did the filtering.
But it is still a small channel. AI tools currently send under 1% of all web traffic (SparkToro). Anyone telling you to abandon search is selling something.
The part most firms will not tell you
You will see a specific claim repeated constantly: GEO improves visibility by 40%.
It does not hold up as a general statement, and it is worth understanding why, because how a firm handles this number tells you a great deal about how they will handle your numbers.
The figure comes from the original 2023 GEO paper, where it describes an upper bound on one metric in one experimental configuration — a setup in which the source document had already been supplied to the model. It measures a position-weighted share of attributed text for a source the system was already given. It does not mean 40% more readers, and it does not mean a 40% higher probability of being retrieved.
A survey published in July 2026 reviewed 45 studies across the field, graded each by evidentiary weight, and placed that claim in its lowest confidence tier — concluding that no reviewed technique produces a stable, cross-platform effect on discoverability (Martinez, arXiv 2607.14035, reported by PPC Land).
The direction of travel is not in doubt. The magnitude of any specific tactic is. Anyone quoting you a guaranteed AI visibility percentage is selling certainty that does not exist yet.
What to actually do
The good news is that the work is unglamorous and largely the same regardless of which platform wins.
Get the content out of the containers machines cannot read. Enumerate every PDF, image flyer, and text-in-graphic on your site. Anything a buyer needs in order to specify, compare, or decide has to exist as plain text on a page.
Answer real questions in self-contained passages. One question, one heading, one complete answer directly beneath it. If a paragraph only makes sense when you have read the three above it, it will not be lifted.
Publish the facts only you can state. Prices. Hours. Response commitments. Capabilities and their limits. Dietary handling. Territory. What you do not do. Every one of those is a question someone asks a machine, and the business that published the answer wins it.
Fix the structured data. Organization, LocalBusiness or Restaurant, Product, FAQPage, Article. Consistent entity information across every surface you appear on.
Consider llms.txt. A plain-text file at your site root offering a curated map of your content, proposed at llmstxt.org. It is not yet an adopted standard and no major engine has committed to honouring it. Cheap to publish, does no harm — worth doing, not worth believing in.
Then measure inclusion, not ranking. Because your rank report will not tell you whether you appear in the answer.
A ten-minute test you can run right now
Open ChatGPT, Perplexity, and Google's AI mode. Type the question your buyer would type — not your company name. The unbranded one. Who is the best commercial roofing contractor for hospitals in my area. Who should I hire to prepare my manufacturing business for sale. Where can I get barbecue catering near me tonight.
See who comes back.
Most companies have never done this. It takes ten minutes and it is frequently the most uncomfortable ten minutes of the quarter — particularly when the answer names three competitors with a fraction of your history.
Then run the second test. Pick your three most important facts: a capability, a specification, a service area. Can you find each one as plain text on a page? Or does it exist only inside a PDF, an image, or a video?
If any answer is the second, your content is not the constraint. Your container is.
The part that has not changed
None of this is a reason to panic, and it is not a new discipline requiring a new vendor.
Being clear about what you do, who you serve, and why you are worth choosing has always been the work. What changed is that the audience now includes machines, and machines are less forgiving than people. A human will squint at a badly organized page and work it out. A retrieval system will not.
Which means the companies winning here are mostly the ones that were already good at explaining themselves, and finally made that explanation machine-readable.
We test this for companies as a matter of course — twelve real buyer searches, run against live engines, showing exactly where you appear and who takes the answers you should own. It is part of the Outside-In Analysis. No cost, and it needs nothing from you but your domain.