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What Is LLM SEO? A Plain-English Definition

What is LLM SEO? A plain-English definition, how it overlaps with AEO and GEO, a real B2B example, and the few things that actually make a difference.

By Mehdi Hassan4 min read

The short answer

LLM SEO is the practice of making your website and brand easy for large language models such as ChatGPT, Claude, Gemini and Perplexity to find, understand and cite when they answer questions. It's also called LLMO. In practice it overlaps almost entirely with AEO and GEO: clear answers, crawlable pages and consistent mentions.

Key takeaways

  • LLM SEO, LLMO, AEO and GEO describe nearly the same work under different names.
  • LLMs answer from training data and from live web searches, so both your site and mentions count.
  • Many AI crawlers don't run JavaScript, so server-rendered text is the first technical requirement.
  • Ahrefs found 97% of llms.txt files got zero requests. Skip the hacks.
  • TripleDart's 2026 study found homepages, not blogs, drew most AI-attributed B2B leads.

Part of Web Design, SEO and AEO Glossary: 50 Terms Explained Simply

What is LLM SEO?

LLM SEO is search optimization aimed at large language models instead of, or as well as, a traditional results page. The goal is that when someone asks an AI assistant a question in your category, the model knows your company, describes it correctly and, when it searches the web, cites your pages.

An LLM learns about you in two ways. Some knowledge comes from training data, which is fixed until the next model version. The rest comes from live retrieval, where the assistant searches the web and reads pages before answering. LLM SEO covers both, which is why it involves your site and what others write about you. It's listed with its sibling terms in our SEO and AEO glossary.

Is LLM SEO different from AEO and GEO?

LLM SEO is not meaningfully different from AEO and GEO. The three names come from different camps and stress different surfaces, but the work they recommend is the same, and it rests on ordinary SEO. Google's own guidance says optimizing for AI features is just SEO.

Term

Named after

What it stresses

LLM SEO / LLMO

The model (ChatGPT, Claude, Gemini)

Being known and cited by assistants

AEO

The answer engine

Writing direct, quotable answers

GEO

Generative engines

Visibility inside generated responses

SEO

The search engine

Crawlability, relevance, authority

Our advice: pick one name internally and stop chasing acronyms. If you want the full playbook under one label, read the answer engine optimization guide.

What does LLM SEO involve in practice?

LLM SEO in practice comes down to four things: pages machines can read, answers machines can quote, an identity machines can recognize, and mentions that confirm it.

  1. Server-render your content. Many AI crawlers don't execute JavaScript. A marketing site built as a client-side app can look empty to them; see fixing a React SPA for SEO.
  2. Allow the right bots. Check robots.txt lets Googlebot, OAI-SearchBot and PerplexityBot crawl the pages you want cited.
  3. Answer first. Open each section with the direct answer, then the detail.
  4. Be a clear entity. Consistent name, description and profiles. See what is entity SEO.
  5. Earn mentions. Engines cite sources that others also reference.
Sources cited per answer, ChatGPT vs Gemini (Semrush AI Visibility Index)
~15 vs ~3
Share of AI-referred sessions from ChatGPT in TripleDart's B2B study
72%
llms.txt files that got zero requests (Ahrefs)
97%

What does LLM SEO look like on a real B2B site?

On a real B2B site, LLM SEO mostly shows up on the homepage and pricing page, not in a special AI section. TripleDart's study of 28 B2B SaaS companies in Q1 2026 found homepages took 31.9% of LLM citations and 81.7% of AI-attributed leads.

Example: what an assistant can read on our own site

Our site is built in Next.js and server-rendered, so an assistant that fetches a page gets the full text in the HTML, not a blank shell waiting for JavaScript. The pricing section states fixed numbers in plain sentences: a $6,000 landing page, an $8,000 website for up to six pages, a $6,000 monthly retainer.

If someone asks an assistant what a studio like ours charges, there's a quotable fact to retrieve. We don't claim any specific assistant cites it for any specific prompt. The point is structural: a page with no stated facts gives the model nothing to say about you.

How do you check whether LLM SEO is working?

You check LLM SEO with a mix of referral data and manual prompt checks, because no tool shows you every AI answer. Set up a GA4 channel group for referrals from chatgpt.com, perplexity.ai, claude.ai, gemini and copilot. Once a month, run the 20 to 30 questions your buyers really ask and note whether you're named, and what is said. Add "how did you hear about us?" to your forms, because many AI-influenced buyers arrive later through branded search, which you'll see more clearly in entity SEO for startups.

Frequently asked questions

What does LLMO stand for?
LLMO stands for large language model optimization. It's another name for LLM SEO: the work of making your brand and pages easy for AI assistants to find, understand and cite. You'll also see AEO, for answer engine optimization, and GEO, for generative engine optimization. The recommended practices behind all of these labels are almost identical.
Can I pay to appear in ChatGPT answers?
Not in the organic answers. ChatGPT, Claude and Perplexity choose sources based on what they retrieve and what they learned in training, not on payment. Some platforms are experimenting with labelled ads, which are separate from the cited sources. The way into the answers themselves is the same as in search: be a clear, credible source that others reference.
How long does LLM SEO take to work?
Live retrieval can pick up a new or improved page once it has been crawled and indexed, so changes that affect web search can show up relatively quickly. Training data is slower: what a model learned about you only updates with the next model version. That's why fresh, crawlable pages and ongoing mentions matter more than a one-off optimization project.
Do I need a separate LLM SEO agency?
Usually not. Most of the work is good SEO, clear copy and a technically sound site, which a strong web team or SEO partner already covers. Be cautious of anyone selling AI-specific tricks such as llms.txt files or special schema as the main deliverable. Ask what they'll change on your pages and how they'll measure it.

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