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llms.txt checker
Enter a site. We fetch its llms.txt, check it against the published format, try a sample of its links, and tell you what to change.
Or try one:
What it checks
The format at llmstxt.org is short: a title, a one-line summary, then sections of links. The checker tests each part.
- A title on the first line. One # heading with the site or product name. It is the only part the format requires.
- A summary. A line starting with > before the first section.
- Sections of links. ## headings, each with a list written as a dash, the page name in square brackets, the address in round brackets, and an optional note.
- Link lines that start with the link. Inside a section, a tool reading the file as a list may skip a line that opens with prose.
- Full addresses. A relative path leads nowhere when the file is read on its own.
- Notes on the links. Optional in the format, and often the difference between a useful entry and a bare title.
- Size. Past about 100 links the file is closer to a sitemap than a guide. That threshold is our judgement, not part of the format.
- Whether the links load. We try up to 12, spread across the file.
- How it is served. As text, not as a web page.
What we found on 60 well-known sites
On 14 November 2026 we ran this on the same 60 sites as our robots.txt check. Twelve refused the request or did not answer, which left 48 clear answers. Of those, 19 have an llms.txt.
They are not spread evenly: 10 of 14 software companies and 6 of 9 developer tools have one, against 2 of 9 shops, 1 of 7 reference sites and none of the 9 news sites.
Of the 19 files, 5 pass every check here: Shopify, Target, Vercel, Cloudflare and Netlify. Nine list more than 100 links. Three are over 100 KB; Salesforce's is 781 KB and 2,857 links with no title or sections, and Zendesk's is 724 KB and 3,133 links. Notion's opens with the summary and has no title line. Mailchimp's and Etsy's are written as prose and headings with no link lists at all.
That last group is a reminder that the format is a proposal. Etsy's file is a readable briefing for an assistant and may serve its purpose better than a tidy list would. A warning here means "this differs from the published format", not "this is broken". The results are published for anyone who wants to check them.
What a pass does not mean
It means the file is well formed. It does not mean any assistant reads it. We have found no AI company saying its assistant uses llms.txt to decide what to cite, and the one experiment we know of, by Otterly, found crawlers barely fetch the file. If you have no file yet, the generator drafts one from your sitemap.
Questions
- My file has warnings. Do I need to fix them?
- Only the first two matter much: a title, and links that load. The rest are differences from the published format, and several large companies' files have the same ones. Fix what makes the file easier to read.
- Can I check a file that is not at the root of the site?
- Yes. Paste the full address ending in llms.txt and that file is checked instead of the one at the root.
- Why did the check say my site refused the request?
- Your firewall turned away an unfamiliar bot. That is common and says nothing about your file. Allow the request, or check the file by pasting its contents into a Markdown preview.
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Updated 14 November 2026.