The crawler question for ChatGPT is OAI-SearchBot (search) and GPTBot (training). Blocking is a real option with a real cost, and the two directions are not symmetric. ChatGPT answers from model weights first and reaches for the web when the question looks fresh, local or specific. Its search index is Bing-derived, so a page Bing has never indexed is effectively invisible to it no matter how well it ranks in Google.
How ChatGPT actually decides
ChatGPT answers from model weights first and reaches for the web when the question looks fresh, local or specific. Its search index is Bing-derived, so a page Bing has never indexed is effectively invisible to it no matter how well it ranks in Google.
Its citations skew toward encyclopedic and reference sources: published analyses put Wikipedia at roughly 47.9% of its top citations. In practice that means the surfaces worth auditing first are Wikipedia, established news and reference sites, vendor documentation, G2 and review aggregators.
The method, in order
Know which agent does what: OAI-SearchBot (search) and GPTBot (training). Training access and answer-time retrieval are usually separate controls, and blocking the wrong one achieves the opposite of what was intended.
Decide what you are protecting. Blocking reduces the chance of being quoted without attribution; it also reduces the chance of being recommended at all.
Consider the asymmetry. Being absent from ChatGPT is easy to cause and slow to undo, even here, where retrieval is live, reputation lags access.
If you do block, block deliberately and document it, so a future traffic investigation does not spend a week rediscovering it.
Re-check after any robots.txt change that the agent you meant to allow is still allowed.
The honest caveat
It is the slowest of the six to notice a new page, because a Bing-derived index has to find you first. Sites that only ever submitted a Google sitemap routinely discover they are absent here.
Cituna checks ChatGPT daily alongside the other five engines, ChatGPT, Perplexity, Gemini, Claude, Grok and Google AI Overviews, on the $39 Starter, and pairs the result with Google Search Console so a change here can be tied to real clicks. We do not track Microsoft Copilot.
Drafted with AI assistance from our own research and Search Console data, and reviewed by Rahul A before publishing. Rules and prices change; check the linked official source before you act.