Will blocking AI crawlers hurt my Google rankings?

Blocking Google-Extended affects generative features, not classic Search indexing. Blocking Googlebot itself does affect Search. The scan reports what your configuration allows so you can decide deliberately.

Do I need an llms.txt file as well?

It is optional and not yet widely honoured, but it is cheap to publish and it makes your site easier to summarise. We provide a template on the templates page.

Free check · Powered by the full LLMao scan

robots.txt Checker for AI Search

See how your crawl configuration reads to AI assistants — checked inside the full LLMao analysis, not by a separate one-off script.

This runs the complete LLMao scan — the same engine, methodology and scoring used everywhere on the site. You get the full report; we simply open it on the part you came here for.

What a robots.txt file actually controls

robots.txt is a public, advisory file at the root of your domain. Well-behaved crawlers read it before fetching anything else and respect the allow and disallow rules for their user agent. It does not secure anything — it signals intent.

A permissive starting point

User-agent: * with Allow: / lets every compliant crawler in.
Add a specific block per crawler only when you want different behaviour for it.
Keep a Sitemap: line pointing at your real sitemap URL.
Do not use robots.txt to hide private pages — use authentication.

Common mistakes we see in scans

A leftover Disallow: / from a staging environment.
Blocking /assets or /_next, which strips the page of the resources needed to render it.
Directives with a typo in the user-agent name, which are silently ignored.
A robots.txt returning a 404 HTML page with a 200 status code.

What LLMao checks for ai crawler accessibility

These are real tests from the LLMao methodology — the same ones that run in every scan, covering Technical Accessibility, Content Freshness.

AI Crawler Access

Technical Accessibility

robots.txt allows GPTBot, ClaudeBot, PerplexityBot, Google-Extended

JavaScript Dependency

Technical Accessibility

Content accessible without excessive JavaScript rendering

Meta Description

Technical Accessibility

Present, descriptive, and within character limits

Social & OG Metadata

Technical Accessibility

Open Graph and Twitter Card metadata present

The same scan also examines content structure, readability, schema.org markup, entity definition, authority & trust signals, citation & source quality — you always get the complete report. See the full methodology.

Frequently asked questions

Keep reading

AI crawler checkerCheck whether your website is reachable by AI and search crawlers as part of a complete AI visibility analysis.AI crawlersA plain reference to the crawlers behind AI search, what they respect, and how to verify your own configuration.llms.txt Explained: What It Is, Who Reads It, and How to Write Onellms.txt is a small markdown file at your site root that tells AI assistants what your site is and where the important pages live. Here's what it does, what it doesn't do, and a template you can ship today.

All articles Methodology How it works

One scan. Your complete AI readiness report.

Crawler access, content structure, structured data, entity clarity, metadata, trust signals and more — 8 categories, 35+ tests, one report you can save and rescan.

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