1. What is LLMs.txt?
LLMs.txt is a simple Markdown file placed in your website root (e.g., example.com/llms.txt). It contains a curated list of content relevant to large language models like ChatGPT. This includes product overviews, service pages, or FAQs.
Unlike a sitemap, this file does not list everything. It focuses on reliable, high-signal content that models can use to answer questions about your business. Markdown makes it readable by both machines and people.
Example:
# Our Company
> Digital services for small businesses since 2015
## Core Pages
- [Product Overview](https://...): Clear summary
- [FAQ](https://...): Common questions
## Additional
- [Press Info](https://...)2. Compared to sitemap.xml
| Item | sitemap.xml | LLMs.txt |
|---|---|---|
| Audience | Search engine crawlers | Language models (e.g., ChatGPT, Perplexity) |
| Scope | All public URLs (hundreds possible) | Focused selection (usually 10-30 URLs) |
| Format | XML | Markdown |
| Purpose | Helps with indexing | Helps models find reliable context fast |
Sitemap.xml serves search engines. LLMs.txt addresses AI tools and provides a clear entry point into your content.
3. Adoption as of May 2025
| Source | Estimate | Notes |
|---|---|---|
| Majestic Million scan | ~105 sites | ~0.011% of top sites |
| Public directories | 170-680 sites | depending on dataset |
| WordPress | Plugins exist | e.g. “Website LLMs.txt” plugin |
Still rare but easy to implement. Teams adopting it now stand out.
4. Why it may matter for your team
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Brand accuracy in AI results: You choose what models see first. Less chance they pick up outdated pages.
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Clear ownership: Helps define what counts as stable, evergreen content across team members.
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Usage rules are visible: You can specify whether content is okay for training, inference, or neither.
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Low effort: One Markdown file, simple to host, easy to keep up to date.
5. LLMs.txt vs. LLMs-full.txt
A second version exists: llms-full.txt. It is not part of the original spec, but some use it.
| LLMs.txt | LLMs-full.txt |
|---|---|
| Link list and short descriptions | Full content of each linked page, in one file |
| Small (few KB) | Large (100 KB to several MB) |
| Most marketing sites | Only for very small sites or technical docs |
| Edit links as needed | Rewrite the full file after every content change |
If you manage a typical business site with multiple sections, llms.txt is easier to handle and scales better.
6. How to implement it
| Week | Task | Role | Notes |
|---|---|---|---|
| 1 | Identify key pages | Content lead | Aim for 10-30 evergreen links |
| 1 | Write Markdown file | SEO / tech | Follow standard layout |
| 2 | Upload and test | Dev / web admin | Check for HTTP 200 OK response |
| 3 | (Optional) add .md versions of core pages | Content ops | Cleaner structure for model parsing |
| Monthly | Review after key updates | Team | Maintain like sitemap.xml |
7. Things to keep in mind
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Major AI vendors do not officially require or follow LLMs.txt yet, but the spec is gaining visibility.
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Measurable traffic or ranking effects are unclear. Most evidence so far is anecdotal.
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The format may evolve. Variants like
llms-ctx.txtare being discussed, so leave room to adjust.
Final notes
LLMs.txt does not solve everything. But it is a clear and manageable step for teams that want to flag their most useful content and make it easier for AI tools to access it properly. It is easiest when your site is built on a headless architecture where content is already structured and easy to export. If you do not have a dedicated developer on hand, our website subscription team can handle implementation for you.