Free llms.txt checker
Check whether your site has a valid llms.txt - the file that gives AI tools a curated guide to your content - and whether it's formatted the way the spec expects.
We check /llms.txt at the address you enter. No signup.
What is llms.txt?
llms.txt is a proposed convention - a markdown file at the root of your site (like robots.txt) that points AI tools to your most important content in a clean, easy-to-read form. It typically has an H1 with your site or project name, a short summary, and markdown links to your key pages.
It's still an emerging standard and support varies, but adding one is low-effort and forward-looking. It sits alongside the more fundamental question of whether AI crawlers are even allowed to read your pages - see our AI crawler accessibility checklist.
Go further
An llms.txt is one small part of AI visibility. To see how ready your whole page is for AI search - can ChatGPT and Perplexity read it, are your business profiles linked - run a free AI visibility check, or a full website health scan. New to the terms? The glossary explains them in plain English.
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