Free llms.txt Validator
Check whether your /llms.txt actually follows the spec — not just that it exists. We validate the title, summary, sections, that every listed link resolves, and whether llms-full.txt is present, then score it.
What is llms.txt?
llms.txt is an emerging standard: a Markdown file at the root of your site (/llms.txt) that gives AI assistants a clean, curated map of your most important content. Where robots.txt tells crawlers what they may access, llms.txt tells AI models what matters — and points them to readable versions of it.
What a valid llms.txt needs
- An H1 with your site or project name (the first line:
# Your Site). - A short blockquote summary (
> one line about what you do) right underneath. - Sections (
## Docs,## About…) of Markdown links to your key pages. - Every listed link should resolve (HTTP 200) and be on your own domain.
- Optionally, an llms-full.txt with the full text of those pages for deeper context.
Don’t have one yet? Build a valid file with our free llms.txt generator.
Frequently asked questions
Is the llms.txt validator free to use?
Yes, it is completely free with no signup. Enter any URL and we fetch and validate its /llms.txt (and /llms-full.txt) against the spec, then score it.
Do I actually need an llms.txt file?
It is optional. llms.txt is an emerging convention, not yet used by every AI engine and not a ranking factor, but adoption is growing and it is low-effort to add. Solid, crawlable on-page content still matters far more.
Why does my llms.txt score low even though the file exists?
Presence alone is not enough. Common gaps are a missing H1 title or blockquote summary, no labelled sections, listed links that 404 or point off-domain, or no llms-full.txt. Fix the failing checks above and re-run to raise the score.
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