Does anyone actually use llms.txt? What the evidence says

Does llms.txt work? It depends on what you mean by "work." If you mean "will it get my business mentioned in ChatGPT or Google's AI answers," the evidence so far says no, not on its own. If you mean "is anyone reading these files at all," the answer is yes, but mostly coding tools and SEO crawlers, not the AI search assistants most business owners care about.

We run a directory and validator for llms.txt files, so you might expect us to oversell it. We'd rather you made a decision with the facts in front of you. Here's what the public evidence says as of October 2026, and where it leaves you.

What Google has said

Google has been the clearest of the big companies, and its answer is that Google Search doesn't use llms.txt.

• April 2025: Google's John Mueller wrote on Reddit that, as far as he knew, none of the AI services had said they use llms.txt, and that server logs show they don't even check for it. He compared it to the old keywords meta tag: a site owner's claim about what the site is about, which a search engine can check by looking at the site itself (Search Engine Journal coverage).
• July 2025: At a Google Search Central event, Gary Illyes said Google doesn't support llms.txt and isn't planning to (Search Engine Land coverage).
• In its own documentation: Google's guide to generative AI features in Search says you don't need new machine-readable files, AI text files or Markdown to appear in Google Search, including its AI features, because Google Search doesn't use them. It adds that making them for other services is fine, but they will neither help nor harm your visibility in Google Search.

So if Google's AI Overviews are your main concern, llms.txt isn't the lever. Google's own advice is that normal SEO practices apply.

What OpenAI, Anthropic and Perplexity have said

Very little. As of October 2026, none of them has published documentation saying their assistants read other websites' llms.txt files when answering questions. Some of them publish llms.txt files for their own developer documentation, which tells you they find the format useful for docs, but that's different from saying their search products use yours.

This is the honest gap: absence of an announcement isn't proof the files are ignored, but it means anyone promising a ranking benefit is guessing.

What server-log studies found

The most useful evidence comes from people who looked at real traffic, because a server log shows exactly who asked for /llms.txt and who didn't.

Ahrefs: most files are never requested

In June 2026, Ahrefs published an analysis of 137,210 domains using its web and bot analytics data for May 2026. About 28% of those domains published an llms.txt file, and 97% of those files received no requests at all that month.

Among the small share of files that were requested, most traffic came from bots, and only about a fifth of the bot requests came from AI systems. SEO audit tools and general crawlers made up a bigger share. The detail we found most telling: Claude Code, Anthropic's coding assistant, fetched more llms.txt files than all the AI search bots combined, while PerplexityBot accounted for about 1% of requests.

SE Ranking: no link to AI citations

In November 2025, SE Ranking looked at around 300,000 domains and found that about 10% had an llms.txt file. It found no relationship between having one and how often a domain was cited in answers from major AI assistants. When the researchers removed llms.txt from their model, its predictions got slightly better (Search Engine Journal coverage).

A caution about smaller studies

You'll also find individual site owners sharing logs that show an AI crawler fetching their llms.txt often. Those reports can be real for that site, but one site isn't a trend, and crawlers fetch all sorts of files. We'd put more weight on the large studies above.

Who does use llms.txt

The clearest use today is developer documentation. When a programmer asks an AI coding assistant to help with a library or an API, the assistant (or the developer) can pull the docs' llms.txt to find the right pages quickly. That matches the Ahrefs finding that coding agents were the most active readers.

It also explains why llms.txt support spread fastest through documentation tools. The llmstxt.org proposal lists docs platforms such as Mintlify and GitBook among the tools that generate the file automatically, alongside website tools like Yoast SEO, All in One SEO and Wix.

For a bakery, a dental practice or a law firm, the audience reading the file, as of October 2026, is much smaller. That's the honest picture.

So why spend 20 minutes on one?

Given all that, here's why we still think a small business site can reasonably have an llms.txt, as long as expectations are set correctly.

• It's cheap. A good file takes about 20 minutes, or a couple of minutes with a generator. On WordPress, popular SEO plugins can create it for you. There's no ongoing cost.
• It can't hurt your Google rankings. Google says so in its own documentation.
• Agents and tools that do read it get a clean summary. AI coding tools, browser agents and custom-built assistants can read any public file. If one does read yours, it gets your name, what you do and your key pages without wading through menus and pop-ups.
• The exercise is useful on its own. Writing the file forces you to decide which 5 to 10 pages matter most and to describe your business in one clear sentence. That sentence belongs on your homepage and your Google Business Profile too.
• Things may change. AI companies haven't ruled it out, and the format costs little to keep up. Just don't build your plans around that possibility.

Where to put your effort instead

If you have limited time, these matter more for how AI tools describe you, according to what Google, OpenAI and Anthropic have actually published:

1. Let the crawlers in. OpenAI says sites must allow OAI-SearchBot to be eligible for ChatGPT's search results, and Anthropic says blocking Claude-SearchBot or Claude-User may reduce your visibility in Claude's search answers. Check that your robots.txt and security settings aren't blocking them by accident.
2. Be indexable in normal search. Google says a page must be indexed and eligible for a snippet to appear as a link in AI Overviews or AI Mode.
3. Write clear pages. Say what you do, where, for whom and at what price, in plain text that loads without JavaScript.
4. Keep your facts consistent. Same name, address, phone and hours on your site, your Google Business Profile and directory listings.

Our free AI readiness check looks at several of these for you: crawler access, content visible without JavaScript, structured data, your sitemap and your page titles and descriptions.

If you do publish one, make sure it works

A file that returns an error page or a broken format is worse than pointless: it's a small job you thought was done. Run yours through the llms.txt validator for a score and a plain list of fixes. If you're new to the format, start with our plain-English guide to llms.txt.

Bottom line: as of October 2026, there's no good evidence that llms.txt gets a business mentioned by AI search tools, and Google says it doesn't use it. Coding tools do read it, it costs little, and writing one clarifies your message. Spend 20 minutes on it, check it works, then put your real effort into crawlable, clear, consistent pages.