AEO vs SEO vs GEO: What Is Different and What to Fix First

What SEO, AEO, GEO and AIO each mean

AEO is the older of the new terms. It grew out of featured snippets and voice search, where one answer is read out or shown above the results. GEO was named in a 2023 academic paper that tested how content changes affect what generative engines cite. AIO has no settled meaning: some people use it for optimising for AI in general, others for Google's AI Overviews specifically, so ask what someone means before you buy it.

The aim behind all three is the same: when someone asks a question, your business should be the source the answer comes from, whether that answer is a blue link, a snippet or a paragraph written by an AI.

What AEO, GEO and SEO share

Most of the work overlaps. AI answer systems mostly retrieve pages from a search index, or crawl the web in a similar way, then summarise what they find. If a page cannot be crawled, cannot be indexed or does not answer the question clearly, it will not be used by either kind of system.

• Crawlability. The page returns 200, is not blocked in robots.txt and has its content in the HTML rather than only after JavaScript runs.
• Indexing. Google's AI Overviews and AI Mode draw on pages in Google's index. Google states there are no extra technical requirements beyond being indexed and eligible to show a snippet. Copilot draws on Bing's index.
• Clear answers. A direct answer near the top of a section, under a heading that matches the question, helps both a featured snippet and an AI summary.
• Trust signals. Named authors, real business details, links and mentions from other sites, and accurate content help pages rank and help AI systems choose a source.
• Structured data. JSON-LD describing the business, products and articles makes facts unambiguous for every system that reads it.

What is genuinely different for AI answers

There are a few real differences, and they are worth knowing so you can ignore the rest of the noise.

The passage point matters most. AI systems quote fragments. A paragraph that starts with It depends, or relies on the previous section to make sense, is hard to quote. A paragraph that opens by answering the question in one sentence, then adds detail, is easy. See content extractability and AEO content structure.

How to check where you stand

Start with access. Check that the main AI search crawlers are not blocked by your robots.txt or your firewall:

curl -s https://example.com/robots.txt

for ua in "Googlebot" "bingbot" "OAI-SearchBot" "PerplexityBot" "Claude-SearchBot"; do
  printf "%-18s " "$ua"
  curl -s -o /dev/null -w "%{http_code}\n" -A "$ua" https://example.com/
done

Every line should print 200. A 403 for one crawler usually means a security plugin, Cloudflare bot rule or server rule is blocking it. Then check your logs for real visits, since a test from your own machine does not prove the crawler gets through:

sudo grep -E "OAI-SearchBot|PerplexityBot|Claude-SearchBot|bingbot" /var/log/nginx/access.log \
 | awk '{print $1, $4, $7, $9}' | tail -20

Next, check the content is in the HTML. Fetch a key page with curl and search for a sentence from its main text. If the sentence is missing, the page relies on JavaScript to render it, and some AI crawlers do not run JavaScript. See JavaScript-only content.

Finally, ask the AI tools your customers use the questions you want to be the answer to, and note who is cited. Repeat monthly with the same prompts, because answers vary from one run to the next.

The key robots.txt and markup changes

Search crawlers and training crawlers are usually separate. You can allow AI search, which can cite and link to you, while deciding separately about training:

# Search and answer crawlers: allow
User-agent: OAI-SearchBot
Allow: /

User-agent: PerplexityBot
Allow: /

User-agent: Claude-SearchBot
Allow: /

# Model training crawlers: your choice
User-agent: GPTBot
Disallow: /

User-agent: Google-Extended
Disallow: /

Google-Extended controls whether Google may use your content for Gemini models. It does not remove you from Google Search or AI Overviews; those follow normal Googlebot and snippet rules such as nosnippet. See robots.txt AI blocks.

Then make the business facts explicit with structured data that matches the page:

{
  "@context": "https://schema.org",
  "@type": "LocalBusiness",
  "name": "Example Bakery",
  "url": "https://example.com/",
  "telephone": "+44 1632 960961",
  "sameAs": ["https://www.facebook.com/examplebakery"]
}

A worked example

Example Bakery wanted to appear when people asked an AI assistant for celebration cakes in its town. An agency had pitched a separate GEO package. Before buying it, the owner checked the basics.

The curl loop showed 403 for OAI-SearchBot and PerplexityBot: a security plugin was blocking unknown bots. The cakes page ranked 14th in Google, its main text was loaded by a JavaScript slider, and the only answer to how much a celebration cake costs was a contact form.

The fixes were ordinary SEO and AEO work: allow the search crawlers, move the text into the HTML, add a short pricing section that opened with a direct answer, add LocalBusiness markup and get listed by two local wedding directories. Within three months the page ranked 4th, and the bakery was named in Perplexity and ChatGPT answers for the same questions. No separate GEO package was needed.

The fix, step by step

Edge cases worth knowing

• Opting out of AI Overviews. Google offers no separate switch; nosnippet and max-snippet limit AI use but also your normal snippets. See opting out of AI Overviews.
• Fewer clicks, more influence. Being cited can reduce clicks for simple questions while increasing brand searches later. Watch branded queries in Search Console.
• Answers change. AI responses vary between runs and users, so one check proves little.
• Wrong facts about you. If an AI system states incorrect details, fix the source: your site, your profiles and the directories it may be reading. See AI hallucinations.

Keeping SEO, AEO and GEO aligned

• Recheck robots.txt and firewall rules after every security plugin or CDN change.
• Write new content with a one-sentence answer at the start of each section.
• Keep business facts identical on your site, profiles and directories.
• Run the same set of AI prompts monthly and log who is cited.
• Review the server log monthly for AI search crawler visits and their status codes.

For the full picture, read the AEO guide and how to get cited by AI search engines.