llms.txt is a small file that tells AI engines like ChatGPT and Perplexity what your site is about. Here's what it is, why it matters, and how to set one up in ten minutes.
You may have heard the term llms.txt thrown around in AI SEO conversations recently and wondered what it actually is.
It is one of the simplest things you can do to help AI engines like ChatGPT, Perplexity, and Claude understand your business. It takes ten minutes to set up. And almost no Australian businesses have one yet, which makes it a quick competitive win.
This guide explains what llms.txt is, why it matters, and exactly how to create one for your site. No technical background required.
For background, the official spec lives at llmstxt.org, and you can see real-world examples like Anthropic's llms.txt or our own Orkkid llms.txt. For the bigger picture on AI search, see our GEO SEO complete guide and the AEO services overview.
What is llms.txt?
llms.txt is a plain text file you place at the root of your website. It tells large language models, the AI behind ChatGPT, Perplexity, Claude, and Gemini, what your site is about and which pages they should pay attention to.
The file works like a signpost for AI. Instead of forcing the AI to crawl your entire site and figure out what matters, llms.txt gives it the summary upfront. Your business name, what you do, your services, and the key pages it should look at first.
It was proposed by AI researcher Jeremy Howard in late 2024 and adoption has been growing through 2025 and 2026. While it is not yet officially mandated by any AI company, ChatGPT, Perplexity, and other engines have started reading these files when they crawl websites.
You can find llms.txt at the URL pattern yoursite.com.au/llms.txt. The file is human readable, which means you can write it in plain English without learning code.
How is llms.txt different from robots.txt or sitemap.xml?
Most websites already have a robots.txt and a sitemap.xml. llms.txt is different from both, though it serves a related purpose.
robots.txt tells search engine crawlers what they are allowed to crawl. It is a permissions file. It says "yes you can read these pages" or "no you cannot read these pages."
sitemap.xml lists every URL on your site so search engines can find them all. It is a directory.
llms.txt explains what your site is about and what matters most. It is a summary. It does not control access or list every URL. It gives AI engines the context they need to understand your business.
You need all three for a fully optimised site. They serve different purposes and complement each other.
Why llms.txt matters for AI search
When ChatGPT or Perplexity tries to answer a question that mentions your industry, the AI does two things. First, it uses what it already knows from training data. Second, it might do a live search to check current information.
In both cases, the AI needs to understand quickly what your site is about. If your homepage is generic or your content is buried, the AI may skip you entirely or get the wrong impression of what you do.
llms.txt fixes that. It is your chance to tell the AI directly. "We are Smith Plumbing. We serve Melbourne metropolitan area. We do residential and commercial plumbing including 24/7 emergency response. Here are our most important pages."
The AI engines that read llms.txt give that information real weight when they answer questions. It is one of the few places on the web where you can speak directly to the model.
For Australian service businesses, the file also helps with local context. You can specify your service area, your specialisations, and your unique angle in plain English.
What goes in an llms.txt file
The file follows a simple Markdown format. Here is the basic structure.
# Your Business Name
> A one or two sentence summary of what your business does and where.
## About
A short paragraph about your business, including how long you have been operating, what makes you different, and who you serve.
## Services
- Service one
- Service two
- Service three
## Service Area
Where you operate. Include cities, suburbs, or regions.
## Key Pages
- [Homepage](https://yoursite.com.au/)
- [About](https://yoursite.com.au/about)
- [Services](https://yoursite.com.au/services)
- [Contact](https://yoursite.com.au/contact)
## Contact
Phone: +61 X XXXX XXXX
Email: hello@yoursite.com.au
That is the basic format. You can extend it with more sections if you want, but keep it focused. The point is to make it easy for AI engines to understand your business at a glance.
A real example: llms.txt for a Melbourne plumber
Here is what a complete llms.txt might look like for a plumbing business in Melbourne.
# Acme Plumbing Melbourne
> Family owned plumbing business serving Melbourne metropolitan area since 2008. 24/7 emergency response, residential and commercial.
## About
Acme Plumbing is a Melbourne based plumbing company founded in 2008. We service residential and commercial customers across the Melbourne metropolitan area, with a focus on emergency response and high quality workmanship. All work guaranteed for 12 months. Licensed and fully insured.
## Services
- Emergency plumbing (24/7)
- Hot water systems (gas, electric, solar, heat pump)
- Drain cleaning and unblocking
- Burst pipe repair
- Leak detection
- Gas plumbing and gas leak repair
- Bathroom renovations
- Kitchen plumbing
- Commercial plumbing maintenance
- Sewer and stormwater repair
## Service Area
Melbourne metropolitan area, including all suburbs within 50 kilometres of the CBD. Common service suburbs include Brunswick, Richmond, St Kilda, Footscray, Box Hill, Frankston, Glen Waverley, Hawthorn, Camberwell, and Doncaster.
## Key Pages
- [Homepage](https://acmeplumbingmelbourne.com.au/)
- [About Us](https://acmeplumbingmelbourne.com.au/about)
- [Emergency Plumbing](https://acmeplumbingmelbourne.com.au/emergency-plumbing)
- [Hot Water Systems](https://acmeplumbingmelbourne.com.au/hot-water)
- [Service Area](https://acmeplumbingmelbourne.com.au/service-area)
- [Reviews](https://acmeplumbingmelbourne.com.au/reviews)
- [Contact](https://acmeplumbingmelbourne.com.au/contact)
## Pricing
Standard service call out: from $99
Emergency after hours call out: from $149
Hot water system installation: from $1,200
Drain cleaning: from $250
All quotes provided in writing before work begins. No surprises.
## Reviews and Reputation
4.9 star average across 240 Google reviews. Featured in the Master Plumbers Association Victoria 2024 awards. Recommended on hipages and Oneflare.
## Contact
Phone: +61 3 XXXX XXXX
Email: hello@acmeplumbingmelbourne.com.au
Hours: 24/7 emergency, Monday to Friday 7am to 6pm for non emergency
ABN: XX XXX XXX XXX
Notice how clear, specific, and dense with information this is. An AI engine reading this knows exactly what the business does, where it operates, what it costs, and how to refer customers to it.
That is the goal. Maximum clarity in minimum words.
Want us to handle this for you? llms.txt setup is included in every AEO engagement. Or book a free citation audit and we will check your llms.txt setup as part of the review.
How to set up your own llms.txt
Here is the step by step process.
Step 1: Draft your file in a plain text editor
Open Notepad on Windows or TextEdit on Mac. Use the template above as a starting point. Replace the example content with your own business details.
Keep it under 500 words for most businesses. Long files dilute the signal. Be specific and clear.
Step 2: Save the file as llms.txt
Save it with the exact filename llms.txt. Make sure the file extension is .txt and not .txt.txt or .doc. Many beginners make this mistake on Windows because the system hides file extensions by default.
Step 3: Upload to the root of your website
The file needs to live at yoursite.com.au/llms.txt, not in a subfolder.
For most platforms, this means uploading via FTP to the root directory of your hosting account. If you use WordPress, you can use a file manager plugin. If you use Webflow, you cannot upload arbitrary files but you can use a redirect trick to serve the content.
For Next.js sites like ours, place the file in the public directory at the root of the project. It will be served at the correct URL automatically.
Step 4: Verify the file is accessible
Open a web browser and go to yoursite.com.au/llms.txt. You should see your text content displayed as plain text in the browser.
If you get a 404 error, the file is not in the right place or has the wrong name. Check both.
Step 5: Test that AI engines can read it
Open ChatGPT and ask "summarise yoursite.com.au based on its llms.txt file." If ChatGPT returns a summary that matches your content, you are set. If not, the file may not be picked up yet, or the AI may not have crawled your site recently. You can also test with Perplexity which is faster at picking up changes.
Be patient. AI crawlers do not visit every site every day. It can take a few weeks before your llms.txt influences AI responses.
Should I add llms.txt to my robots.txt?
Yes, you can reference it explicitly. Add this line to your robots.txt to make it easy for crawlers to find.
LLM-Content: https://yoursite.com.au/llms.txt
This is not strictly required, since AI engines often look for llms.txt at the root by default. But it is good practice and removes any ambiguity.
Does llms.txt help with Google rankings?
Indirectly. Google does not officially read llms.txt as a ranking signal. But Google AI Overviews use the same underlying systems that read llms.txt, so a well written file does help AI Overview visibility.
For pure traditional SEO, llms.txt has no direct effect. But for AI SEO, it is one of the highest leverage things you can do.
Common llms.txt mistakes
A few mistakes show up often. Skip these.
Mistake 1: Making it too long. A 5,000 word llms.txt dilutes the signal. Keep it focused and under 500 words for most businesses.
Mistake 2: Filling it with marketing fluff. "Industry leading solutions delivered with passion" is useless to AI engines. Write specifically. "Plumbing services across Melbourne since 2008" is much better.
Mistake 3: Using the wrong file format. It must be plain text saved as .txt. Not Word, not PDF, not HTML. Plain text Markdown.
Mistake 4: Putting it in the wrong location. It needs to be at yoursite.com.au/llms.txt, not yoursite.com.au/content/llms.txt or any other path.
Mistake 5: Forgetting to update it. When your services change or you add new locations, update the file. AI engines re-crawl periodically and will pick up changes.
Frequently asked questions
Is llms.txt mandatory for AI SEO?
No. ChatGPT, Perplexity, and Gemini will still find and cite your business without one. But having one improves your chances and clarifies what you want the AI to know.
It is one of the easiest wins in AI SEO, so there is little reason not to have one.
Will all AI engines read my llms.txt?
Most major engines have started reading llms.txt files. ChatGPT, Perplexity, and Claude crawl them. Google has not officially confirmed it reads them, though Gemini may use the data.
The standard is still emerging. Adoption is likely to grow through 2026 and 2027.
Can llms.txt block AI engines from using my content?
Not directly. llms.txt is a guidance file, not a permissions file. To control crawler access, use robots.txt with specific rules for GPTBot, ClaudeBot, PerplexityBot, and Google Extended.
llms.txt tells AI engines what is most important. robots.txt tells them what they are allowed to read.
How often should I update my llms.txt?
Every quarter is reasonable for most businesses. Update it whenever your services change, your service area expands, or you launch a new offering. Keep the date roughly current.
Is there a tool to generate llms.txt automatically?
A few generators have started appearing online but most are basic. The best approach is to write it yourself or have a marketer write it for you. The 30 minutes you spend gets you a much better file than any generator.
What if my hosting platform does not let me upload arbitrary files?
For platforms like Wix or Squarespace that lock you out of the root directory, the workaround is to host the file elsewhere and use a redirect from your domain. Or move to a platform that gives you full file access.
For most service businesses, this is one more reason to use a developer friendly platform like WordPress, Webflow, or a custom built site.
If you want help setting up llms.txt and the rest of your AI SEO foundation, book a free citation audit. We test your visibility across thirty AI prompts and give you a step by step plan.
For the broader strategy, read the GEO SEO complete guide or learn more about our Answer Engine Optimization services.