llms.txt Validator and Generator
Check an llms.txt file against the llmstxt.org format line by line, or build a new one from a simple list of links. Nothing you paste leaves this page.
What llms.txt is, and is not: llms.txt is a proposal published at llmstxt.org (first version September 2024, version 2 in August 2026) for a Markdown file that points AI agents to a site’s key pages. Google’s AI guidance says files like this “will neither harm nor help your site’s visibility or rankings in Google Search, as Google Search ignores them.” Think of it as a low-cost map for agents, not a ranking tool.
Paste your llms.txt
Result
Your site
Your llms.txt
Save it as llms.txt in your site root, so it opens at yoursite.com/llms.txt. “## Optional” is the spec’s name for links an agent can skip when it needs a shorter context.
The format in one picture
The spec lists the parts in a fixed order. Only the H1 is required. Each link in a section is a Markdown list item with a link, optionally followed by a colon and a note.
# Site name > One-sentence summary of the site Optional details in plain paragraphs or lists (no headings). ## Section name - [Link title](https://example.com/page/): optional note ## Optional - [Link title](https://example.com/more/)
On WordPress, a generated llms.txt can return a 404 when permalinks, server rules or a leftover file get in the way. Find the cause in one command.
Let WordPress keep it up to date
Free plugin: serves an llms.txt that rebuilds when you publish, skips noindex and password-protected pages, and lets you add custom links.
llms.txt validator: common questions
What does a valid llms.txt file look like?
A valid llms.txt starts with an H1 holding the site name, which is the only required part. The llmstxt.org spec then allows a blockquote summary, plain details without headings, and H2 sections. Each section is a Markdown list of links written as – [Title](URL), optionally followed by a colon and a short note.
Does llms.txt help my Google rankings?
No. Google's guidance on AI features says files like llms.txt will neither harm nor help a site's visibility or rankings in Google Search, because Google Search ignores them. The llmstxt.org proposal describes the file as a map for AI agents that need a site's key pages, not as a ranking signal.
Where do I put the llms.txt file?
Put llms.txt in the root of your site so it opens at yoursite.com/llms.txt. Version 2 of the llmstxt.org spec also allows a file in a subpath, such as /docs/llms.txt, which covers only the pages under that path. When more than one file applies, the spec says agents should use the most specific one.
What is the Optional section in llms.txt?
An H2 section named Optional holds secondary links. The llmstxt.org spec says agents can skip those links when they need a shorter context. Put core pages such as pricing, docs or contact in normal sections, and put archives, blogs or extra reading under ## Optional.
Is a byte-order mark (BOM) allowed in llms.txt?
Yes. Version 2 of the llmstxt.org spec, modified on August 10, 2026, lists an optional byte-order mark as the first part of the file, before the H1. Text such as YAML front matter between — lines is not allowed before the H1, so this validator reports it as an error.