LLM optimization
LLM SEO: free tool and step-by-step guide
LLM SEO is the work of getting large language models such as ChatGPT, Claude and Gemini to name your brand and cite your pages when buyers ask them for advice. Test where you stand now: GPT, Claude and Gemini models answer one of your buyers' questions, and you see whether each answer names your domain or cites your site.
How it works
Measure before you optimize
01
Pick a question that matters
Use a question close to a purchase, the kind a buyer asks an assistant before choosing, and add your business name and website.
02
Three models answer
Small models from the GPT, Claude and Gemini families answer through their APIs, each able to search the web with Rank.ai's search tool, which returns Google results.
03
Read how each one treats you
Per model: whether the answer names your business, how often it cites your site, the pages it cited, and the start of the answer.
Why it matters
How to do LLM SEO
LLM SEO, short for large language model search engine optimization, makes your brand the one an AI assistant names and your page the one it links. The same work goes by several names. They describe one job from different angles:
| Name | What it emphasises |
|---|---|
| LLM SEO, LLM optimization (LLMO) | The models themselves: ChatGPT, Claude, Gemini, Perplexity |
| Generative engine optimization (GEO) | The academic term, from a 2023 research paper on how generative engines pick sources |
| Answer engine optimization (AEO) | Direct answers: featured snippets, voice assistants, AI answers |
| AI SEO, AI search optimization | The broad umbrella, sometimes also used for using AI tools to do SEO |
Our generative engine optimization guide covers the research and the full method. This page is the short, practical version.
How a language model decides who to name
An answer draws on two layers, and each needs different work.
- Training data. What the model learned before release decides whether it knows your brand and connects it with your category. You change it slowly, by being written about widely, and it only updates when the model is retrained.
- Live search. For questions about products, prices, local businesses and anything recent, assistants search the web, read a few pages and write from them. This layer changes as soon as a better page is indexed and ranking.
The search layer is where most LLM SEO pays off. In Rank.ai’s sample of 11,726 answers from ChatGPT, Claude and Gemini with web search on, ChatGPT ran a web search for 100% of buyer questions, Claude 98.4% and Gemini 95.6%. The models also shortened the question before searching: buyer questions averaged 11.7 words, the searches ChatGPT and Claude ran averaged 6.5 words, and Gemini’s 5.1 (Rank.ai analysis of 11,726 AI answers, May to October 2026). So the page that gets read is the one ranking for that short search, which is often a different phrase from the one the buyer typed.
LLM SEO vs SEO
| SEO | LLM SEO | |
|---|---|---|
| The result | A position in a list of ten links | A written answer that names a few brands and cites a few pages |
| What wins | Relevance, links, page experience | Ranking for the model’s own searches, quotable facts, being named on the pages it reads |
| Measured by | Rank tracker, Search Console | Asking the same questions on a schedule and counting mentions and citations |
| Stability | Positions move over days and weeks | The same question can name different brands from one run to the next |
The two overlap heavily. Ahrefs found that 38% of URLs cited in Google’s AI Overviews also rank in Google’s top 10 (Ahrefs, 863,000 SERPs, 2026), so a page nobody can find in search rarely gets cited. The AEO vs SEO entry goes deeper on the differences.
LLM SEO in seven steps
- Write down the questions buyers ask.Twenty to fifty, in their words: “best payroll software for a 20-person company”, “X vs Y”, “how much does X cost”. These are your keywords now.
- Get a baseline. Run each question through the tool above, or through ChatGPT, Claude and Gemini yourself, and record who is named and which pages are cited.
- Let the crawlers in. Allow search crawlers such as OAI-SearchBot, PerplexityBot, Googlebot and Bingbot in robots.txt and at your CDN. The AI crawler checker tests this in seconds.
- Publish one clear article per question. Answer it in the first two sentences, then back the answer with specifics a model can lift: prices, numbers, named methods, dates. Use headings that repeat the question.
- Cite your sources and add data.In the original GEO research, adding statistics, quotations and citations raised a page’s share of the answer by 30% to 40%, while keyword stuffing did worse than no edit (Aggarwal et al., KDD 2024).
- Get named on the pages models read.Review sites, “best of” lists, directories and forum threads. Branded web mentions correlated with AI Overview visibility at 0.664, against 0.218 for backlinks, across 75,000 brands (Ahrefs, 2025).
- Measure again, on a schedule. One answer is one sample. Count how often you are named across many days before you call something a win or a loss.
What the data says about getting named
- Most answers name nobody.61% of ChatGPT answers to buyer questions named no business, and so did 61.9% of Gemini’s and 63.4% of Claude’s. When an answer does name businesses it tends to name a list: about one in five named five or more (Rank.ai analysis of 11,726 AI answers, May to October 2026).
- Engines disagree. The brand tracking each question was named in 11.0% of Gemini answers, 8.1% of Claude answers and 6.4% of ChatGPT answers in the same sample. Checking one engine misses most of the picture.
- Reddit is the most-cited site, at 4% of citations. Reddit took 4.01% of 74,761 citations, YouTube 2.09% and Wikipedia under 0.3% on every engine. The rest is spread across thousands of sites: Claude alone cited 2,577 different domains in the sample.
- Schema alone shows no lift. Adding JSON-LD changed ChatGPT citations by +2.2%, statistically no different from zero, across 1,885 pages tested against 4,000 controls (Ahrefs, 2026). Keep structured data accurate for Google, and spend the effort on the article.
- llms.txt is optional.Google says you don’t need new AI text files to appear in its AI features (Google Search Central). Our llms.txt entry covers the trade-offs.
More figures, each with its source, are on our GEO and AEO statistics and AI search statistics pages.
How to measure LLM SEO
Track four numbers for each question: how often you are named (mention rate), how often your pages are linked (citation rate), your mentions as a share of all brands named (share of voice), and who is named in your place. Answers vary from run to run, so read them as rates over weeks. The LLM visibility entry defines each metric.
This tool gives you one reading. For the full picture in one go, the free AI gradeasks ChatGPT, Claude and Gemini 12 questions your customers ask and scores you out of 100. To keep measuring, Rank.ai’s AI visibility plans ask ChatGPT, Claude and Gemini every question you add once a day, then write and publish the articles for the questions you lose. For a step-by-step version focused on one engine, read how to rank in ChatGPT.
Free tools
More free tools
AI visibility checker
Ask ChatGPT, Claude and Gemini one question and see whether each answer names your domain or cites your site.
ChatGPT SEO tool
Ask an OpenAI model a buyer question and see whether the answer names your domain or cites your site.
AI search visibility checker
Check one search across ChatGPT, Claude and Gemini in a single run.
AI Overview checker
See whether Google shows an AI Overview for your keyword and whether it cites your site.
AI Overviews tracker
Check one keyword for an AI Overview now; Rank.ai's rank tracker notes an Overview on every keyword you track.
AI crawler checker
See which of 14 AI crawlers and tokens your robots.txt blocks, and which of them feed AI search.
All free tools
AI visibility checker, Google Business Profile audit, Maps rank checker, schema validator and more.
Frequently asked
What is LLM in SEO?
What is SEO for LLMs called?
How is LLM SEO different from regular SEO?
Are LLMs good at SEO?
Is SEO dead now with AI?
Which models does this tool test?
How fast can I change what an LLM says about me?
Does Rank.ai track this every day?
See if AI names you when customers ask who’s best.
Enter your website. In about two minutes, Rank.ai asks ChatGPT, Claude and Gemini 12 questions your customers ask and grades how often they name you.
- Your grade out of 100How often AI names you, cites your site, and how high it ranks you.
- Who gets namedEvery competitor in the answers, most named first.
- The pages AI readsThe sources behind each answer.
- Three fixesWhat to fix first, with a brief for the first page.