Introducing the llms.txt Checker and Generator

If you've read our guide to llms.txt for UK shops, you'll know the file is simple: a short Markdown list of your most useful pages. It's also easy to get slightly wrong, with a missing heading, a relative link or a section with nothing in it.

The short answer: our free llms.txt Checker and Generator checks an existing llms.txt file against the format proposed at llmstxt.org, or builds a starter file for a shop or service site from a simple form. Checking and generating happen in your browser. It's also honest about the file: Google Search says it ignores llms.txt, so treat it as a map of your site, not a ranking switch.

Here's why we built it, what it does and how to use it.

Why we built an llms.txt checker

Since we added our Robots.txt Tester, the next question we've heard most is about llms.txt. Some SEO tools now report it as missing, plugins can create one for you, and Shopify serves one on every store by default.

What most people want to know is simple. Is my file in the right format, and if I don't have one, what should go in it? A plain Markdown file is easy to write, but there's no built-in way to check it. So we built one, and added a generator for anyone starting from scratch.

What the checker does

Paste your file, drop a .txt file onto the editor, use "Upload .txt", or click "Load example" to see how it works first. The tool reads it against the llms.txt proposal and shows two views:

• Outline: the site name, summary and each section with its links, so you can see the file the way a tool reading it would.
• Issues: a list of errors and warnings, with a count of each.

The checks cover the problems we see most often:

• Headings: no H1 site name, more than one H1, content before the H1, and H3 or smaller headings, which aren't part of the proposal.
• Links: list items that aren't in the - [name](url): note format, URLs that aren't absolute, links that don't point at http or https pages, and duplicate URLs.
• Sections: any section heading with no links under it.
• The file itself: a file that looks like HTML rather than Markdown, which usually means you've copied an error page, a file that doesn't look like Markdown at all, and a file over 100 KiB, which is too long for a short map of the site.

When the file passes, it tells you it matches the proposal well enough to publish.

What the generator does

Switch to Generate and fill in a short form:

• Site: your site name, a one-line summary and an optional line or two of detail.
• Sections: add as many as you need, each with a title and rows for a link name, URL and short note. Add or remove sections and links as you go.
• Presets: "UK shop preset" fills in typical shop sections such as collections, delivery and returns. "Service business preset" starts with services and contact details.

Copy the generated file, download it as llms.txt, or use "Load into editor" to run it through the checker before you publish it.

How to use it

1. Open the llms.txt Checker and Generator.
2. Add your current file. Paste it in or drop it on the editor. Or type your domain into "Fetch from a domain" and click Fetch.
3. If the fetch is blocked, tick "Fetch via aamservices.uk" and try again. Most sites don't let other websites read their files from a browser, so the direct fetch is best effort only. With the box ticked, our server loads the same public file for you. Or use "Open llms.txt" to view it in a new tab, then "Paste from clipboard".
4. Read the Issues list and fix each error in the editor.
5. No file yet? Use Generate. Pick a preset, swap in your own pages, then copy or download the result.
6. Publish it at your site root, so it opens at yourdomain.co.uk/llms.txt.

If your live file returns a 403 or never appears, the tool includes short notes for the common platforms. On OpenCart, the default .htaccess blocks text files other than robots.txt. On Shopify, you customise the file with an llms.txt.liquid theme template. On WordPress, Yoast SEO can generate it. Our llms.txt guide walks through each one step by step.

What stays in your browser and what our server fetches

Like our other free tools, checking and generating happen on your device. What you paste, type, drop or read from the clipboard stays in your browser.

By default, fetching a live file is a direct request from your browser to https://yourdomain/llms.txt. If the site blocks that, tick "Fetch via aamservices.uk" and our server loads the same public file for you, just as the Robots.txt Tester does. Only the domain goes to our server, never what you paste, and it only fetches /llms.txt from public hostnames. You can choose to remember your last input, and if you do, it's saved in your browser only.

llms.txt is a map, not a ranking switch

We built the tool because people asked for it, not because llms.txt will change your traffic. Google's guide to optimising for generative AI features in Search says Google Search ignores llms.txt files, and that creating one "will neither harm nor help your site's visibility or rankings in Google Search". Google's John Mueller has compared it to the keywords meta tag, and Gary Illyes has said Google doesn't support it.

No major AI engine has confirmed that it reads other sites' llms.txt files either. If you want to control which AI and search bots can crawl your shop, that's robots.txt, and the Robots.txt Tester will show you what your current file allows.

If you do publish an llms.txt, keep it short, accurate and up to date. That's what the checker is for.

FAQ

Is the llms.txt Checker and Generator free?

Yes. It's free to use, like the rest of our tools.

Is my file uploaded anywhere?

No. Anything you paste, type or drop stays in your browser. If you fetch a live file, your browser requests it directly from that site, unless you tick "Fetch via aamservices.uk". Then our server fetches the site's public llms.txt for you.

Why can't the tool fetch my llms.txt?

Most sites block other websites from reading their files in a browser. Tick "Fetch via aamservices.uk" and try again, or open the file in a new tab with "Open llms.txt", copy it, then use "Paste from clipboard". If the server fetch fails too, check that the file opens at your site root and doesn't return a 403 or 404.

Does a clean result mean AI tools will use my file?

No. It means the file follows the llms.txt proposal. Google Search ignores the file, and no major AI engine has confirmed that it reads other sites' files.

Can it generate a file for a service business, not just a shop?

Yes. Use "Service business preset" to start with services and contact details, then edit the sections to suit your site.

Why does my OpenCart llms.txt return a 403?

OpenCart's default .htaccess blocks text files other than robots.txt. Our llms.txt guide shows the one-line change that allows it.

Is llms.txt the same as robots.txt?

No. robots.txt tells crawlers which paths they may fetch. llms.txt is a reading list of pages and doesn't allow or block anything.

Try the llms.txt Checker and Generator and see if your file is in good shape. If you'd like help with how search engines and AI tools see your site, our SEO and AI search work starts with the technical basics, or you can get in touch and tell us what you're working on.