What is GEO? Generative engine optimization vs SEO vs AEO, explained simply

Three acronyms now describe overlapping work. GEO, generative engine optimization, is about AI-written answers. AEO, answer engine optimization, is the older name for getting your page used as the direct answer. SEO is the discipline both grew out of. This guide separates what is genuinely new from what is the same work with a new label.

What is GEO?

GEO means improving the chance that a generative AI system — ChatGPT search, Perplexity, Gemini, Claude, or Google’s AI Overviews and AI Mode — can find your page, read it, and cite or mention it in an answer. The term comes from a 2023 research paper, GEO: Generative Engine Optimization, by Pranjal Aggarwal and colleagues, later accepted to KDD 2024. The authors built a benchmark of queries, rewrote source pages in different ways, and reported that some changes could “boost visibility by up to 40% in generative engine responses” on that benchmark. They also found that “the efficacy of these strategies varies across domains.” It is a useful study measured in a research setup. It is not a measurement of how any commercial engine treats your site today.

What is AEO?

AEO, answer engine optimization, is the name the industry used for making a page the one a search engine or voice assistant quotes as the answer: a featured snippet, a spoken reply. Today it is used almost interchangeably with GEO. Where people do draw a line, AEO leans toward the answer passage on your page, and GEO toward the whole journey from crawler access to being cited. You will also see “AI SEO” and “LLMO” for the same idea. No standards body defines any of them.

GEO vs SEO vs AEO: what actually differs?

	SEO	AEO	GEO
Where you show up	Ranked links in search results	The quoted answer: a snippet or a spoken reply	Inside an AI-written answer, as a citation or a mention
Who reads your page	Search crawlers such as Googlebot and Bingbot	The same search crawlers	Search crawlers plus each AI company’s own, such as OAI-SearchBot, Claude-SearchBot and PerplexityBot
What success looks like	Clicks from a ranking	Your wording used as the answer	Your page cited, or your brand named
How it is measured	Search Console clicks, impressions and position	Mostly the same reports	Search Console’s generative AI report for Google; for other engines, asking the questions and recording the answers

What does Google say about GEO?

Google’s AI optimization guide answers it directly: from Google’s point of view, “optimizing for generative AI search is optimizing for the search experience, and thus still SEO.” It adds that “You don’t need to create new machine readable files, AI text files, markup, or Markdown to appear in Google Search,” and that “Structured data isn’t required for generative AI search, and there’s no special schema.org markup you need to add.” For AI Overviews and AI Mode, Google’s AI features page says a page must be indexed and eligible to show with a snippet, and that “There are no additional technical requirements.”

That covers Google. ChatGPT, Claude and Perplexity run their own crawlers and indexes, and that is where GEO adds work that classic SEO does not.

GEO is mostly SEO done properly, plus one new question: can each AI company’s crawler actually read the page?

Adnan Arodiya, Crawlwise

What is genuinely new in GEO?

• More crawlers to let in. OpenAI says “Sites that are opted out of OAI-SearchBot will not be shown in ChatGPT search answers.” Anthropic says disabling Claude-SearchBot “may reduce your site’s visibility and accuracy in user search results.” Perplexity runs PerplexityBot to “surface and link websites in search results.” A robots.txt written years ago with only Google in mind may block all three. See which AI crawlers to allow.
• Mentions on other sites show up more clearly. Ahrefs analysed 75,000 brands and found that branded web mentions correlated with AI visibility in ChatGPT, AI Mode and AI Overviews at 0.66 to 0.71. Correlation is not cause, but it fits what answer engines do: they quote sources, and the sources they quote talk about brands.
• Answers are written, not ranked. There is no position three. You are named, cited, both, or neither, and the same question can get a different answer tomorrow, so one check is a snapshot.
• One question becomes many searches. Google describes AI Mode breaking a question into subtopics and searching for each — query fan-out — so a page can be pulled in for a sub-question it answers well.

What does GEO work look like in practice?

1. Let the crawlers in. Check robots.txt and your CDN for each search crawler. In the Crawlwise AI Crawler Access Report (top-10000 run, 2026-Q4: the first 10,000 domains of the Cisco Umbrella top-one-million list, each probed once on October 1, 2026), 4,159 of 10,000 domains (41.6%) refused at least one of the 17 AI crawlers tested. The list ranks hostnames by DNS popularity, so it includes API, CDN and update hosts that never serve a web page, and only the homepage path was probed. Treat the shares as a description of that list, not of the whole web.
2. Put the answer in the server HTML. Most AI vendors do not document JavaScript rendering for their crawlers, so the safe assumption is that they read what your server sends.
3. Answer first. State the answer in the opening lines of the section that covers the question, then explain it.
4. Show where facts come from. Link your sources, and say who wrote the page and when it last changed.
5. Be mentioned where answers come from. Find the sites engines cite for your topic and earn a real mention there.
6. Measure honestly. Use Search Console for Google, and repeated checks of your own questions for the other engines.

What GEO is not

It is not a file: Google says Search ignores llms.txt and similar files (details here). It is not a score: a single “GEO score” blends signals with weights nobody outside the tool can check, which is why Crawlwise does not publish one. And it is not a trick that works on one engine forever. The durable part is the plain part: access, clear answers, evidence, and a reputation other sites repeat.

Interest in the topic is real. Ahrefs’ June 2026 trends report puts US searches for “ai overview optimization” at about 900 a month, up 625% year over year. The vocabulary will keep shifting; the work above will not. For the words you will meet along the way, see the GEO and AI search glossary.

How Crawlwise tests this

The free AI crawler checker fetches a URL as each AI crawler and reports which ones got through, and why when one did not. A full audit reads the page those crawlers receive: whether the text is in the source HTML, whether the opening passage answers the question, the snippet controls, structured data and sources. To see whether ChatGPT names your brand for a question, the free AI mention checker runs one snapshot; tracking over time and the “why not” diagnosis are part of AI visibility on a plan.

Every check, what counts as a block, and what the checks cannot see are written up on the methodology page.

What a plan actually costs

The free tools stay free. You can open them, run them, and leave without an account. A plan is for the moment you want the report saved, a few sites watched, or the same checks from the API. The price on this table is the price at checkout. A yearly plan is ten months of the monthly price, so two months are on us.

A single-page audit is about 1.25 credits, and that includes the live probe of answer-engine crawlers. You see the estimate before anything runs. If a hold is not used, it comes back to your balance. Extra credits, when you already subscribe, are $9.99 for 20.

Frequently asked questions

Is GEO replacing SEO?

No. Google says that, from its point of view, optimizing for generative AI search is still SEO. GEO adds two things on top: letting each AI company’s crawler in, and checking AI answers directly, because ranking reports do not show them.

Is AEO the same as GEO?

In practice, mostly. AEO is the older term for being the quoted answer; GEO is used for AI-written answers broadly. Neither has an official definition, so read what a vendor means by it rather than the label.

Do I need an llms.txt file for GEO?

Not for Google: its AI optimization guide says Search ignores AI text files and they neither help nor harm. No major answer engine documents using llms.txt to choose citations.

Can anyone guarantee an AI citation?

No. You can remove the reasons you are not cited — a blocked crawler, a page that never states the answer — and then measure what happens. A guarantee is a promise about a system nobody outside the vendor controls.

What is a sensible first GEO step?

Check whether the AI crawlers can fetch your homepage and your most important page. If one is blocked, fix that before you touch any content, because nothing else can work while it is blocked.

Sources

Every page below was read on 2026-10-29. Vendors change prices, limits and documentation without notice, so check the original before you act on a detail.

• Aggarwal et al. — GEO: Generative Engine Optimization (arXiv 2311.09735, accepted to KDD 2024)
• Google Search Central — AI optimization guide
• Google Search Central — AI features and your website
• OpenAI — Overview of OpenAI crawlers
• Anthropic — Does Anthropic crawl data from the web, and how can site owners block the crawler?
• Perplexity — Perplexity crawlers
• Ahrefs — 10 SEO trends I’ve seen firsthand in 2026 (Ryan Law, June 18, 2026)
• Crawlwise — The AI Crawler Access Report (top-10000 run, 2026-Q4)