GEO: Getting ChatGPT and Perplexity to Cite Your Content

By LanDi ·Published September 27, 2026

What is GEO?

The term GEO (Generative Engine Optimization) comes from a 2023 paper by researchers at Princeton University and elsewhere, “GEO: Generative Engine Optimization.” The study found that adding citations, quotations, and statistics to content noticeably increases the chance of being cited by generative engines, with the authors reporting improvements of up to about 40%.

Put simply: SEO competes for rankings; GEO competes for the citation link in an AI answer.

How does AI find and cite content?

When most AI assistants answer a question that needs up-to-date information, the process roughly looks like this:

1. Rewrite the user’s question as a search query.
2. Find candidate pages through a search index (their own, or Bing, Google, etc.).
3. Fetch the page content and pick out passages that answer the question.
4. Generate the answer and attach source links.

This means two things: traditional SEO is still the foundation (step 2), and your content must be readable by AI crawlers and break down into citable passages (step 3).

Which AI crawlers exist, and should I block or allow them?

Companies usually separate their “training” crawlers from their “search” crawlers:

Sources: OpenAI crawler documentation, Google’s list of crawlers.

Recommended strategy:

• If you want AI to cite you: you must allow the search crawlers.
• If you don’t want your content used for training: you can block only the training crawlers. This doesn’t affect being cited in search.
• Check your CDN settings: Services like Cloudflare have a “block AI bots” toggle that blocks crawlers at the firewall level, which you’d never see from robots.txt. If your site uses a CDN, be sure to check this setting.

Why does server-side rendering matter for GEO?

Googlebot executes JavaScript, but most AI crawlers don’t. If your site is purely client-side rendered (for example, just an empty <div id="root"> with content generated by JavaScript), AI crawlers see a blank page.

Checking is easy: use your browser’s “View Page Source” (not the Elements panel in DevTools) and see whether the article content is in the HTML. This site’s health check tool also counts the visible words in the raw HTML.

How do I write content AI wants to cite?

1. Give concrete data: “LCP should be under 2.5 seconds” is more likely to be cited than “your site should be fast.”
2. Cite authoritative sources with links, so AI can cross-check.
3. Show a clear author and date: State the author, their background, and the last-updated date, and mark them up with structured data.
4. One point per paragraph: AI extracts content paragraph by paragraph, so each paragraph should make sense on its own.
5. Offer exclusive information: First-hand experience, test data, and original research are things AI can’t get anywhere else.

Is llms.txt worth doing?

llms.txt is a format proposed in 2024: a Markdown file placed at the site root that lists the site’s most important content so large language models can read it easily.

The honest status: it is a community proposal, the major AI search engines have not publicly committed to reading it, and Google has said it isn’t needed. This site includes one because the cost is very low (it’s generated automatically at build time), but don’t expect it to bring traffic.

How do I measure GEO results?

• Ask the AI directly: Ask ChatGPT, Perplexity, and Gemini your target questions and see whether you appear among the cited sources. Keep a fixed set of questions and record the results regularly.
• Check traffic sources: Look at referral traffic in your analytics from domains such as chatgpt.com and perplexity.ai.
• Check server logs: See whether AI crawlers are visiting and which pages they fetch.

For more measurement methods, see Post-Launch Measurement: Search Console, Bing & AI Citations.

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