Paste your site and see, robot by robot, whether ChatGPT, Claude, Perplexity and Google's AI are let in, and whether your firewall turns them away anyway.
Reads your public robots.txt and home page. Takes a few seconds. The address is not stored.
Most advice lumps every AI robot together: block them all or allow them all. They do different jobs.
The common mistake is a blanket Disallow: / for every AI name, copied from a list, which shuts out search robots along with training ones. In our study of 731 websites, 20% of English-language sites (35 of 172) blocked AI bots in robots.txt. ChatGPT still named 32% of the sites that block AI crawlers and 34% of the open ones, because it also answers from what other sites say about a business. So opening robots.txt is worth doing, but it is not enough on its own.
If you want assistants to find you but would rather not feed model training, this is the shape. Put it above any general rules and keep your sitemap line.
User-agent: OAI-SearchBot User-agent: ChatGPT-User User-agent: Claude-SearchBot User-agent: Claude-User User-agent: PerplexityBot User-agent: Perplexity-User Allow: / User-agent: GPTBot User-agent: ClaudeBot User-agent: Google-Extended User-agent: Applebot-Extended User-agent: CCBot Disallow: / User-agent: * Allow: / Sitemap: https://example.com/sitemap.xml
Robots.txt is a request, not a lock. Well-behaved robots follow it; it does nothing against a scraper that ignores it, and a firewall can block a robot that robots.txt allows. That is why the check above looks at both.
Being readable is the entry ticket, not the result. The free OperStack check reads your site the way an assistant does, scores it out of 100 and asks ChatGPT the questions your buyers ask, to see whether it names you or someone else.
A search or answer robot reads your page so an assistant can find it and quote it to a person now: OAI-SearchBot for ChatGPT search, PerplexityBot, Claude-SearchBot. A training robot collects text for future models: GPTBot, ClaudeBot, CCBot. OpenAI, for example, says that blocking OAI-SearchBot keeps a site out of ChatGPT search answers, while disallowing GPTBot only means the content should not be used for training (OpenAI crawler documentation).
That is a business decision, not a technical one. Blocking GPTBot, ClaudeBot, Google-Extended or Applebot-Extended does not remove you from today's answers. Google says Google-Extended does not affect inclusion or ranking in Google Search (Google documentation), and Apple says pages that disallow Applebot-Extended can still appear in its search results (Apple documentation).
You cannot do it with a robot name. Google says AI Overviews and AI Mode follow the same controls as ordinary search: Googlebot in robots.txt, and snippet controls such as nosnippet and max-snippet on the page (Google: AI features and your website).
Because a firewall or bot protection can turn robots away even when robots.txt lets them in. We open your home page as a normal browser and again under each robot's name. If the browser gets the page and the robot gets a refusal twice, we flag it. We say "may" because our request only borrows the robot's name: protection that checks the real robot's published IP addresses can treat the real one differently. Your server log has the final word.
Not always. OpenAI says robots.txt rules may not apply to ChatGPT-User because a person started the request, and Perplexity says Perplexity-User generally ignores robots.txt for the same reason (Perplexity crawler documentation). Anthropic describes its three robots on its help page.
No. The check runs while the page loads and nothing is written down: no account, no cookie, no database. We send at most 12 requests to your site: robots.txt signed OperStackTools with a link to oper-stack.com/tools/, and the home page once as a normal browser and once under each robot's name for the firewall test.
Built by Maksim Shchegolev, founder of OperStack. Free, no account, no cookie. The address you check is not stored.
OperStack