--- title: "llms.txt Checker: Does This Website Have llms.txt? - Web Aloha" description: "Free llms.txt checker. Instantly verify if any website has a valid, well-formed llms.txt file. Check format, structure, and completeness for AI search readiness." canonical_url: "https://webaloha.co/tools/llms-txt-checker/" markdown_url: "https://webaloha.co/tools/llms-txt-checker.md" date_modified: "2026-07-12T00:00:00.000Z" --- # llms.txt Checker Last updated: Jul 12, 2026 Check if any website has a valid llms.txt file. Verify existence, format, structure, and completeness: the AI-readable index that helps ChatGPT, Perplexity, and other AI systems understand your site. ## What Is llms.txt? llms.txt is a plain text file placed at the root of a website, for example, `yoursite.com/llms.txt`, that helps large language models (LLMs) and AI systems understand the site's structure and most important content. Think of it as a curated, AI-readable index of your site. While [sitemap.xml](https://webaloha.co/tools/sitemap-checker-and-validator/) lists all your URLs for search engine indexing, llms.txt tells AI systems *which pages matter most* and *what they contain*, in plain language. The format was proposed in 2024 and has quickly gained adoption as part of the broader [GEO (Generative Engine Optimization)](https://webaloha.co/generative-engine-optimization-geo-complete-guide/) toolkit. ## What This Checker Tests When you enter a domain, this tool checks the following: - **File existence:** Is there a file at `/llms.txt` on the root domain? - **HTTP status:** Is it returning 200 OK? A 404 means no file exists. - **Content type:** Is it served as `text/plain` as the spec recommends? - **H1 header:** Does the file start with an H1 (site name) as required by the format? - **Description present:** Is there a short description following the H1? - **Sections (H2):** Are pages organized under H2 section headers? - **Linked entries:** Does the file contain Markdown-formatted links with descriptions? - **llms-full.txt:** Does the site also provide the optional full-text companion file? ## The llms.txt Format A valid llms.txt file follows this structure: \# Site Name Brief 1-3 sentence description of what the site does and who it serves. ## Services - \[Service Page\](https://example.com/services/): What this page covers. - \[Another Service\](https://example.com/other/): Description. ## Blog / Guides - \[Key Article\](https://example.com/article/): What this article covers. ## Tools - \[Free Tool\](https://example.com/tools/tool/): What the tool does. Use our [free llms.txt Generator](https://webaloha.co/tools/llms-txt-generator/) to build a properly formatted file for your site. For a complete guide to the format and strategy, read our [llms.txt Complete Guide](https://webaloha.co/llms-txt-complete-guide/). ## Why llms.txt Matters for AI Visibility AI search platforms like ChatGPT, Perplexity, and Google AI Overviews retrieve and cite content from the web. The clearer and more structured your site appears to these systems, the more accurately and frequently they will reference your business. llms.txt is part of a broader technical foundation for [AI search visibility](https://webaloha.co/geo-services/) that includes: - ✅ **[robots.txt](https://webaloha.co/tools/robots-txt-tester-and-validator/)**, allowing AI crawlers to access your content - ✅ **[Schema markup](https://webaloha.co/tools/schema-markup-validator/)**, structured data for entity and content verification - ✅ **llms.txt**, curated navigation guide for AI systems - ✅ **[Passage-level content](https://webaloha.co/how-to-optimize-content-for-ai-citations/)**: clear, extractable answer blocks Use the [AI Search Visibility Checker](https://webaloha.co/tools/ai-search-visibility-checker/) to get a comprehensive readiness audit that goes beyond just llms.txt. ## Related Tools - [llms.txt Generator](https://webaloha.co/tools/llms-txt-generator/), Create a properly formatted llms.txt file for your site - [AI Search Visibility Checker](https://webaloha.co/tools/ai-search-visibility-checker/), Full GEO readiness audit for your site - [AI Crawler Tester](https://webaloha.co/tools/ai-crawler-tester/), Check which AI bots can access any URL - [Robots.txt Tester](https://webaloha.co/tools/robots-txt-tester-and-validator/), Validate your crawler access rules - [Schema Markup Validator](https://webaloha.co/tools/schema-markup-validator/), Check your structured data - [Sitemap Checker](https://webaloha.co/tools/sitemap-checker-and-validator/), Validate your XML sitemap Next steps ## llms.txt Checker related tools and articles Continue with the closest follow-up checks and guides based on this tool's topic, crawl intent, and optimization workflow. [![AI Search Visibility Checker Tool Online](https://webaloha.co/_astro/tool-ai-visibility.CquCsynE_1mSaDC.webp?dpl=dpl_8RvAS1xqmRGEQGx5EyHZ5bsuaJhu) AI Search Visibility Checker ](https://webaloha.co/tools/ai-search-visibility-checker/)[![llms.txt Generator Tool Online](https://webaloha.co/_astro/tool-llms-checker.VKZNvzJo_ZOlJVb.webp?dpl=dpl_8RvAS1xqmRGEQGx5EyHZ5bsuaJhu) llms.txt Generator ](https://webaloha.co/tools/llms-txt-generator/)[![AI Crawler Tester Tool Online](https://webaloha.co/_astro/tool-ai-visibility.CquCsynE_1mSaDC.webp?dpl=dpl_8RvAS1xqmRGEQGx5EyHZ5bsuaJhu) AI Crawler Tester ](https://webaloha.co/tools/ai-crawler-tester/)[![How to Optimize Your Content for AI Citations](https://webaloha.co/_astro/blog-content-for-ai-citations.DOTnbGDp_Z23pyJS.webp?dpl=dpl_8RvAS1xqmRGEQGx5EyHZ5bsuaJhu) How to Optimize Your Content for AI Citations ](https://webaloha.co/how-to-optimize-content-for-ai-citations/)[![llms.txt: The Complete Guide for 2026](https://webaloha.co/_astro/blog-llms-txt-guide.Cf70Dvir_Iati0.webp?dpl=dpl_8RvAS1xqmRGEQGx5EyHZ5bsuaJhu) llms.txt: The Complete Guide for 2026 ](https://webaloha.co/llms-txt-complete-guide/)[![Why Robots.txt Matters for AI Search and GEO in 2026](https://webaloha.co/_astro/blog-robots-txt-ai-geo.D_4d0VJ2_Z1cXCWI.webp?dpl=dpl_8RvAS1xqmRGEQGx5EyHZ5bsuaJhu) Why Robots.txt Matters for AI Search and GEO in 2026 ](https://webaloha.co/robots-txt-ai-search-geo/) ## llms.txt Checker: FAQ Which URL does the checker request? It takes the hostname from your input and checks https://hostname/llms.txt plus https://hostname/llms-full.txt. Paths, query strings, a typed http scheme, and custom ports are not preserved, so the file is always checked at the HTTPS site root. What counts as an existing llms.txt file? The checker treats HTTP 200 as found. Other statuses are reported as missing. It expects a text/plain Content-Type and flags other types, even though some valid deployments may use another text-oriented media type. Which structure checks are performed? It looks for one H1 line, a following non-heading description line, at least one H2 section, and at least one bullet Markdown link with an absolute HTTP or HTTPS URL. These are simple text-pattern checks, not a full Markdown or llms.txt parser. What does the llms-full.txt badge mean? It only means the root llms-full.txt request returned HTTP 200. The checker does not parse or grade that file's content, and llms-full.txt is optional. Does passing improve rankings or guarantee AI citations? No. llms.txt is a voluntary, evolving convention. A clean file may help a compatible system navigate selected resources, but it does not force crawling, indexing, retrieval, ranking, or citation. Why can the checker fail when the file opens for me? The proxy or direct fallback can time out, encounter bot protection, receive a different CDN response, or be blocked by CORS on the browser fallback. Also confirm the file is publicly available over HTTPS at the exact root path. Which llms.txt issue should I fix first? Serve the intended Markdown as a successful root response, then correct the Content-Type and add a concise H1, description, useful H2 sections, and absolute links to canonical pages. Keep the list curated and update it when important URLs change. What data is sent during an llms.txt check? The hostname is sent to Web Aloha's proxy so it can request the two public text files; if that fails, your browser may try the site directly. The checker displays up to 2,000 characters but does not include application logic that persists the file content. Free 48-Hour Website Audit Not sure what to fix first on your own website? We'll review it and tell you, in plain English. Free & non-obligatory. [Get My Free Audit 💪](https://webaloha.co/free-website-audit/) ## Need Help With Your Website? We help businesses build and optimize their online presence, let's talk. [Explore GEO Services 🤙](https://webaloha.co/geo-services/)