Search “GEO vs SEO” and one of the top results isn’t a vendor blog. It’s an r/SEO thread asking what the real difference is. That’s the right question, because a lot of “GEO” on sale is SEO with a new invoice attached.
The skeptics are half right. Here’s the short version:
For Google’s AI Overviews and AI Mode, GEO is mostly SEO. For ChatGPT, Claude and Perplexity, it isn’t: those assistants cite a largely different set of pages than Google ranks, reached by different crawlers, and you have to measure them differently.
Below: the evidence for that sentence, a practice-by-practice matrix you can hand to your team, and what changes about measurement.
What GEO is (and why AEO and “LLM SEO” are the same thing)
Generative Engine Optimization (GEO) is the work of getting your brand mentioned and your pages cited inside AI-generated answers, as opposed to ranking as a blue link. The term comes from a 2023 research paper by Aggarwal et al., published at KDD 2024, which reported that content changes could raise visibility in generative engine responses by up to 40% in their test setup.
AEO (answer engine optimization), LLM SEO and “AI SEO” describe the same job. Different vendors picked different labels. Don’t let the acronym soup convince you these are three disciplines.
The case that it’s just SEO (and it’s a strong one)
Google itself says so. Its guide to optimizing for generative AI in Search (last updated 10 July 2026) states that optimizing for generative AI search “is optimizing for the search experience, and thus still SEO.” The same page says:
- You don’t need llms.txt, AI text files or special Markdown to appear in Google Search.
- There’s no requirement to break content into tiny chunks for AI.
- Structured data isn’t required, and there’s no special schema for AI features.
- To be eligible at all, a page must be indexed and eligible to show with a snippet.
The data backs Google up for its own surfaces. Ahrefs reports that 76% of AI Overview citations come from pages ranking in the top 10. If you win the Google SERP, you’re most of the way into AI Overviews.
One wrinkle: what wins AI Overviews isn’t only classic link-building. Across 75,000 brands, Ahrefs measured a 0.664 correlation between branded web mentions (linked or not) and AI Overview visibility, against 0.218 for backlinks. Correlation, not proof, but a 3x gap is hard to ignore.
So if your only AI concern is Google, keep doing good SEO and stop buying “GEO packages.”
The case that it isn’t (for everyone except Google)
Now look at the assistants. In the same Ahrefs study of 15,000 long-tail queries (August 2025), only about 12% of URLs cited by AI assistants ranked in Google’s top 10 for the same prompt. Per engine:
| Assistant | Cited URLs that also rank in Google’s top 10 |
|---|---|
| Perplexity | 28.6% |
| Gemini | 8.6% |
| Copilot | 8.2% |
| ChatGPT (in-text) | 8.0% |
Roughly 80% of AI-cited pages didn’t rank anywhere in Google’s top 100 for the original query. That’s not “halfway there.” That’s a different retrieval system.
Two more findings push the same way:
- Different crawlers. OpenAI runs GPTBot for training and OAI-SearchBot for ChatGPT search; sites that block OAI-SearchBot “will not be shown in ChatGPT search answers.” Anthropic splits ClaudeBot, Claude-SearchBot and Claude-User. Perplexity has PerplexityBot plus Perplexity-User, which generally ignores robots.txt. Googlebot access tells you nothing about any of these.
- No JavaScript rendering. Vercel and MERJ’s crawler analysis found GPTBot, ClaudeBot and PerplexityBot don’t execute JavaScript, while Gemini (via Googlebot) and AppleBot do. A client-rendered page can rank fine on Google and be an empty shell to ChatGPT.
My take: the skeptics are right about Google and wrong about the assistants. And the assistants are where your devtool buyers ask “what should I use for X?”
The SEO vs GEO overlap matrix
This is the part to screenshot. Each row is a practice: what it does for each channel, what’s genuinely different, how you’d check it, and how much it matters if you’re a low-authority startup.
| Practice / signal | Matters for SEO | Matters for GEO | What’s actually different | How to measure it | Priority for a small site |
|---|---|---|---|---|---|
| Crawlability and indexing | Yes, table stakes | Yes, table stakes | Nothing for Google AI (must be indexed with a snippet). Assistants run their own indexes. | Search Console coverage; server logs filtered by AI user agents | High |
| robots.txt and AI bot access | Googlebot only | Critical | Separate bots per vendor, and training bots are split from search bots. Blocking GPTBot (training) doesn’t block OAI-SearchBot (search); blocking OAI-SearchBot removes you from ChatGPT search. | Check each AI user agent against your robots.txt and CDN/WAF rules | Highest: do it this week |
| Rendering without JS | Helps, Google renders JS | Critical | GPTBot, ClaudeBot and PerplexityBot read raw HTML only | Compare raw HTML vs rendered DOM for key pages | High if your site is client-rendered |
| Structured data (JSON-LD) | Yes, for rich results | Weak to none for citations | Ahrefs saw no citation lift on already-cited pages; Google says no special schema needed | Rich result reports for SEO; don’t expect citation movement | Low for GEO |
| llms.txt | No | No evidence | Google says AI text files neither help nor hurt in Google Search | Skip it | Skip |
| Backlinks and authority | Core ranking signal | Weaker signal | Brand mentions correlate ~3x more with AI Overview visibility than backlinks | Referring domains for SEO; mentions for GEO | Medium: slow to build |
| Brand mentions (linked or not) | Indirect | Strong | Unlinked mentions on forums, reviews, YouTube and docs count toward being “known” | Brand & keyword mentions tracking across the web | High |
| Content freshness | Query-dependent | Stronger for assistants | AI-cited pages are 25.7% fresher than organic results on average; AI Overviews lean slightly older | Last-updated date vs citation rate per page | Medium: real updates only |
| Content structure / chunking | Clear structure helps | Clear structure helps | Google says no artificial chunking needed; write clearly, don’t slice | Readability, one answer per section | Medium |
| Being cited by third parties | Earns links | Earns citations directly | Assistants often cite the review, thread or comparison page, not you | Which domains the engines cite for your prompts | High: your fastest GEO lever |
| Measurement unit | Rank position, clicks | Mention rate across runs | AI answers vary run to run; a single “AI rank” is noise | Prompt sets run repeatedly per engine (below) | High: set a baseline early |
Sources for the “different” column: OpenAI bots, Vercel/MERJ, Ahrefs schema test, Google’s AI guide, Ahrefs brand study, Ahrefs freshness study.
Two rows deserve a closer look because they’re where most “GEO checklists” are wrong.
Schema. Ahrefs tracked 1,885 pages that added JSON-LD against 4,000 controls (published May 2026). Citations moved +2.2% in ChatGPT and +2.4% in AI Mode, both statistically indistinguishable from zero, and fell 4.6% in AI Overviews. The caveat: every page was already heavily cited, so schema might still matter for pages nobody cites yet. But “add FAQ schema to get into ChatGPT” is not supported by the best test we have. Add schema for rich results, where it earns its keep.
Freshness. Across ~17 million citations, AI-cited content averaged 1,064 days old versus 1,432 days for Google organic results. ChatGPT leaned newest. That’s a reason to genuinely update pages, not to bump dates on unchanged ones.
What to fix first: the access layer
If you do one thing this week, check whether the AI search bots can reach you at all. A blanket “block AI crawlers” rule someone added last year, or a CDN bot-protection setting you never looked at, can shut out OAI-SearchBot and Claude-SearchBot while Googlebot sails through. That’s GEO failing before any content question comes up.
Paste your domain into the robots.txt checker to see which AI user agents your file allows or blocks. Then decide deliberately: blocking training bots (GPTBot, ClaudeBot) while allowing search bots (OAI-SearchBot, Claude-SearchBot, PerplexityBot) is a legitimate middle position.
Second, fetch your most important pages without JavaScript. If the pricing table, the docs content or the product description isn’t in the raw HTML, the non-Google assistants can’t cite it.
How measurement changes
This is where most GEO advice goes vague, and it’s the real reason people call it snake oil. SEO gives you a rank and a click count. GEO gives you neither.
- The unit changes from position to frequency. SparkToro and Gumshoe ran 12 brand-recommendation prompts 2,961 times across ChatGPT, Claude and Google’s AI Overviews and, as Search Engine Journal reported, found under a 1% chance of getting the same brand list twice. How often a brand appeared across runs was far steadier. So a single “you rank #3 in ChatGPT” is one sample of a random process; track mention rate across repeated runs.
- Split by engine. With Perplexity at 28.6% overlap and ChatGPT at 8%, one blended “AI visibility” score hides everything interesting.
- Google’s side now has first-party data. Search Console’s generative AI performance report rolled out to all sites on 31 August 2026, per SEJ. It shows impressions in AI Overviews, AI Mode and Discover’s AI features, but no click data yet: it tells you that you appeared, not why.
The full loop (building a prompt set, running it, logging the cited sources, re-measuring) is in how to rank in ChatGPT. For tools that run prompt sets for you, see our comparison of AI visibility tools, including where each one is the better pick.
Can GEO replace SEO?
No. Lose your Google rankings and you lose most of your AI Overview citations with them, per the 76% figure above. GEO is an extra layer for the assistants, not a replacement. The bigger threat to SEO traffic is zero-click answers eating clicks you already earned, which we cover in AI Overviews are eating your traffic.
What to do if you’re a small site
Low-authority startups have one advantage here: with only ~12% overlap between assistant citations and Google’s top 10, you can get cited by ChatGPT or Perplexity for prompts where you’d never crack page one.
- This week: fix AI bot access and confirm key pages render without JS.
- This month: build a prompt set and get a baseline mention rate per engine, plus your competitors’.
- Ongoing: get mentioned where the engines already look for your category (the domains they cite when you’re absent), and genuinely update the pages that matter.
- Keep doing SEO. It’s still most of the game for Google’s AI surfaces.
Track both in one place
The annoying part of GEO vs SEO isn’t the strategy. It’s that the evidence lives in five tools: rank tracker, Search Console, a prompt tracker, a mentions tool and a robots.txt audit. RunAgents puts Google rankings, AI Overview ownership, per-engine AI citations, AI share of voice against competitors, brand & keyword mentions and AI bot access into one real-time layer, with alerts when a competitor starts getting cited for your prompts. Put your SERP and AI citations side by side and see exactly where Google and the assistants disagree about your category.