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AI Access Tester

Your website's robots.txt file controls which AI crawlers can access your content. If models like ChatGPT, Claude, or Gemini are blocked, they can't learn about your brand — and they can't recommend you. Enter your domain and see exactly who's allowed in.

21
AI Crawlers Checked
11
AI Companies Covered
<5s
Scan Time
AI models blocked from entering a website — illustration showing AI bots standing outside locked gates
How It Works
Free Assessment in Seconds.
01
Enter Your Domain

Type any website URL. No login, no email, no strings attached.

02
Scan For Crawler Access

Centium reads your robots.txt file and checks access rules for 21 AI crawlers across 11 companies.

03
See Your Results

Instantly see which AI models can access your site, which are blocked, and what it means for your visibility.

What We Analyze
Three Categories of AI Access
🧠
AI Training Crawlers

Crawlers that index your content to train the next generation of AI models. Blocking these means AI won't learn from your latest content.

GPTBot, Google-Extended, ClaudeBot, CCBot, Meta-ExternalAgent, Bytespider, DeepSeekBot

🔎
Live Search Crawlers

Crawlers that access your site in real time when users ask AI a question. Blocking these prevents AI from citing your brand during conversations.

ChatGPT-User, OAI-SearchBot, Gemini-Deep-Research, PerplexityBot, Perplexity-User, BraveBot, DuckAssistBot

📇
Search Index Crawlers

Traditional search crawlers that power AI-integrated results in search engines. Essential for appearing in AI Overviews and featured answers.

Googlebot, Bingbot, Applebot-Extended, Amazonbot, Claude-SearchBot

Why AI Crawler Access Matters

When a potential customer asks ChatGPT for a hotel on their vacation, or asks Gemini to recommend a running shoe, the AI model draws on two sources: knowledge it learned during training, and information it finds by searching the web in real time. Both of these mechanisms depend on AI crawlers being able to access your website.

Your website's robots.txt file is the gatekeeper. It's a small text file at the root of your domain that tells web crawlers (including AI-specific ones) what they're allowed to access. Many websites use restrictive configurations, often put into place by IT teams to preserve server traffic. The result is that AI models are silently blocked from your content without anyone on your team knowing it.

The Two Types of AI Crawlers

Training crawlers like GPTBot and ClaudeBot index your website content so it becomes part of the model's knowledge base. When they're blocked, the AI model's understanding of your brand stays frozen in time, or worse, relies entirely on third-party sources you don't control, like review aggregators and forums. Centium measures both what AI can access, and what has been indexed to date in each model.

Live search crawlers like ChatGPT-User and PerplexityBot visit your website in the moment a user asks a question. These are the crawlers that generate real-time citations and drive actual referral traffic. Blocking them means AI will answer questions about your category without ever checking your site for the latest information.

What Happens When AI Can't Access Your Site

If your competitors allow AI crawlers and you don't, AI models will recommend them over you. Not because they're better, but because they're more visible. The AI has more information to work with, more recent data to cite, and more confidence in recommending brands it can actually verify. In a world where AI-assisted purchasing decisions are growing rapidly, robots.txt is no longer just a technical SEO concern. It's a visibility strategy.

Centium Has Entered the Chat.

The AI Access Tester shows you who can enter. Centium shows you what AI actually says about your brand by tracking 600 prompts across five AI models with a competitive analysis, citation tracking, and actionable strategy.

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