llms.txt Explained: What It Is, How to Create One, and Does It Matter?

llms.txt is a proposed standard: a short Markdown file placed at yoursite.com/llms.txt that summarises your website for large language models and points them to your most useful pages. It is easy to create and costs almost nothing, but it is not a ranking factor, and Google has said that Google Search does not use it.

This guide explains where the idea came from, shows a complete example, and covers what actually matters more for AI search visibility.

Where did llms.txt come from?

The llms.txt format was proposed by Jeremy Howard in 2024 and is documented at llmstxt.org. The idea is simple. Websites are built for human visitors, with navigation, scripts, pop-ups and layout that language models do not need. A plain Markdown file could give a model a clean summary of what a site is about and where the key information lives.

It is a proposal, not an official web standard. No standards body requires it, and no major AI search engine has documented that it reads llms.txt when deciding what to cite.

What does an llms.txt file look like?

The proposed format is ordinary Markdown with a small amount of structure:

• An H1 heading with the name of the site or business (one line starting with #)
• A blockquote summary: a short description of who you are and what you do (lines starting with >)
• Optional plain paragraphs with extra context
• Sections with H2 headings (##), each containing a list of links with a short note

llms.txt example for a fictional business

Here is a complete example for an invented plumbing company. The business, address and phone number are fictional.

# Harbourline Plumbing & Heating
> Harbourline Plumbing & Heating is a family-run plumbing and heating company in Sydney, Australia, serving homes and small businesses across the Inner West and Eastern Suburbs since 2011.
Harbourline offers emergency plumbing, hot water system installation and repair, blocked drains, gas fitting and bathroom renovations. Licensed plumbers are available 24/7 for emergencies.
Contact: +61 2 5550 0123 | hello@harbourline.example | 12 Example Street, Marrickville NSW 2204
## Services
- [Emergency plumbing](https://harbourline.example/emergency-plumbing/): 24/7 call-outs for burst pipes, leaks and flooding
- [Hot water systems](https://harbourline.example/hot-water/): installation, repair and replacement of gas, electric and heat-pump systems
- [Blocked drains](https://harbourline.example/blocked-drains/): CCTV drain inspection and high-pressure jetting
- [Gas fitting](https://harbourline.example/gas-fitting/): appliance connections, leak detection and compliance certificates
## About
- [About us](https://harbourline.example/about/): history, team and licences
- [Service areas](https://harbourline.example/areas/): suburbs we cover in Sydney
- [Reviews](https://harbourline.example/reviews/): what customers say
## Help
- [Pricing and call-out fees](https://harbourline.example/pricing/): how quotes and fees work
- [FAQ](https://harbourline.example/faq/): answers to common plumbing questions
- [Contact](https://harbourline.example/contact/): phone, email and booking form
## Optional
- [Blog](https://harbourline.example/blog/): maintenance tips and guides

In the proposal, a section titled “Optional” marks links that can be skipped if a model needs a shorter context. Keep the whole file short and factual. It should read like a clear briefing, not an advert.

Tips for writing yours

• Use the exact business name you use everywhere else.
• Put the most important facts in the summary: what you do, where, and for whom.
• Link to real, indexable pages, not to pages blocked in robots.txt or behind logins.
• Write link notes in plain words that match the page content.
• Keep facts identical to your website, Google Business Profile and directory listings.

Where do you upload llms.txt?

Place the file at the root of your domain so it loads at https://yourdomain.com/llms.txt. A few practical points:

• Save it as plain text with UTF-8 encoding.
• Make sure it returns a normal 200 response, not a redirect to your homepage or a 404 page.
• On WordPress and similar platforms, you can upload it to the site root by FTP or your host’s file manager, or use a plugin that serves it.
• Open the URL in a browser afterwards to confirm it displays as text.

Does llms.txt help SEO or AI visibility?

Here is the honest status:

• Google has said that Google Search does not use llms.txt. Google states there are no special requirements for AI Overviews or AI Mode beyond normal Search eligibility.
• Other major AI search engines, including those behind ChatGPT, Perplexity, Claude and Copilot, have not officially documented using llms.txt.
• No AI company publishes its ranking formula, so nobody can show that llms.txt improves your chances of being mentioned.

So does llms.txt help SEO? There is no evidence that it does. Treat it as a low-cost, optional extra. It does no harm, it takes minutes, and writing it is a useful exercise in describing your business clearly. Just do not expect it to change your rankings or AI mentions on its own, and be wary of anyone selling it as a shortcut.

How is llms.txt different from robots.txt and a sitemap?

The three files are easy to confuse, but they do different jobs.

The key point: llms.txt cannot grant or block access. If your robots.txt blocks OAI-SearchBot, Claude-SearchBot, PerplexityBot, Googlebot or Bingbot, an llms.txt file will not undo that. Access is controlled by robots.txt and your server, not by llms.txt.

What matters more than llms.txt?

If you only have an hour, spend it on the things engines are known to rely on.

1. Crawler access

AI search engines need to reach your pages. Blocking training crawlers such as GPTBot, ClaudeBot or Google-Extended does not remove you from AI search answers, but blocking the search crawlers does. Check your robots.txt and any firewall or CDN bot rules. See how to allow AI crawlers in robots.txt.

2. Indexing in Google and Bing

Googlebot powers Search, including AI Overviews and AI Mode. Bingbot powers Bing and Copilot. If your key pages are not indexed, they are unlikely to appear in those engines’ AI answers.

3. Structured data

schema.org markup such as Organization or LocalBusiness, with properties like address, telephone, openingHours, areaServed and sameAs, gives machines facts in a format they can read reliably. It must match what is visible on the page. See Organization and LocalBusiness schema for AI search.

4. Consistent facts everywhere

Use the same name, address and phone on your website, Google Business Profile, Bing Places, Apple Business Connect and directories. Consistency helps engines match all those mentions to one business. Our guide to entity SEO for AI search goes deeper.

5. Clear pages that answer real questions

Engines retrieve and quote pages that answer specific questions directly. A well-written service page or FAQ will do more than any summary file. See how to write FAQs AI assistants quote.

A 15-minute llms.txt checklist

1. Minutes 1–3: Write the H1 with your exact business name and a one or two sentence blockquote summary: what you do, where, for whom.
2. Minutes 4–8: Add sections for services, about and help, each with links to your most important pages and a short plain note.
3. Minutes 9–10: Check every fact against your website and Google Business Profile: name, address, phone, services, areas.
4. Minutes 11–12: Upload the file to your domain root as UTF-8 plain text.
5. Minute 13: Open yourdomain.com/llms.txt in a browser and confirm it loads with a normal response.
6. Minutes 14–15: While you are there, check that robots.txt does not block AI search crawlers and that your structured data matches your visible content.

Set a reminder to update the file whenever your services, locations or contact details change. An out-of-date llms.txt is worse than none.

How Onxeera helps

You can write llms.txt by hand, or use a generator. Onxeera’s Brand Knowledge tool keeps one fact profile for your business and, on Starter plans and above, outputs an llms.txt alongside a connected schema.org JSON-LD graph, so both come from the same facts. It also checks your website for missing facts and conflicts. To confirm AI search crawlers can reach your site, try the free AI Crawler Checker.

Frequently asked questions

Is llms.txt required for AI Overviews or ChatGPT?

No. Google has said that Google Search does not use llms.txt and that AI Overviews and AI Mode have no special requirements beyond normal Search eligibility. Other major AI search engines have not documented using it. Crawler access, indexing, structured data and clear content matter far more.

Can llms.txt block AI crawlers from my site?

No. llms.txt only describes your site; it does not control access. To allow or block crawlers such as GPTBot, OAI-SearchBot, ClaudeBot or PerplexityBot, use robots.txt and your server or CDN settings. Remember that blocking search crawlers can remove you from AI answers.

Is it worth using an llms.txt generator?

A generator can save time, but review the output carefully. Make sure the business name, summary, contact details and links are accurate and match your website. A file built from your own fact profile is more reliable than one scraped from pages that may contain outdated details.

How often should I update llms.txt?

Update it whenever something important changes: new services, new locations, a new phone number or a redesigned site with different URLs. A quick review every few months is sensible. Outdated facts in any file can add to conflicting information about your business online.