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ChatGPT-User vs Google-Extended

ChatGPT-User and Google-Extended compared on 11 documented fields, from 17 claims, last verified 2026-09-13.

FieldChatGPT-UserGoogle-ExtendedComparison
cites_sourcesnot_documentednot documenteddifferent
honours_crawl_delaynot_documentedn/adifferent
publishes_ip_listyesnodifferent
purpose_documenteduser_fetchpolicy_onlydifferent
reads_llms_txtnot_documentednot documenteddifferent
respects_robots_txtpartialn/adifferent
robots_token_differs_from_uanot documentedyesdifferent
separate_search_and_training_tokensnot_documentedyesdifferent
user_agent_string_fullMozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko); compatible; ChatGPT-User/1.0; +https://openai.com/botnot documenteddifferent
verifiable_by_rdnsnot_documentedn/adifferent
what_it_controlsnot documentedGemini model training and grounding, not Search inclusiondifferent

Differences

FieldChatGPT-User statementGoogle-Extended statement
cites_sourcesOpenAI does not publish whether ChatGPT responses cite pages fetched by ChatGPT-User.not documented
honours_crawl_delayOpenAI does not publish whether ChatGPT-User honours the robots.txt Crawl-delay directive.Google does not publish any Crawl-delay behaviour for the Google-Extended token.
publishes_ip_listOpenAI publishes the IP address ranges used by ChatGPT-User as a JSON file at https://openai.com/chatgpt-user.json.Google publishes no IP list for Google-Extended because Google-Extended has no separate HTTP request user agent string.
purpose_documentedChatGPT-User visits web pages for user actions in ChatGPT and in Custom GPTs.Google-Extended is a standalone product token that controls whether Google uses crawled content to train Gemini models.
reads_llms_txtOpenAI does not publish whether ChatGPT-User reads llms.txt files.not documented
respects_robots_txtChatGPT-User fetches pages in response to user actions in ChatGPT, and OpenAI states that robots.txt rules may not apply to ChatGPT-User fetches.Google-Extended is a robots.txt token that publishers set to control use of crawled content for Gemini training.
robots_token_differs_from_uanot documentedGoogle-Extended is a robots.txt control token and does not correspond to a crawler user agent string.
separate_search_and_training_tokensOpenAI does not document ChatGPT-User as a search or training opt-out token.Google-Extended controls Gemini training use only and does not affect inclusion in Google Search.
user_agent_string_fullChatGPT-User sends the user agent string Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko); compatible; ChatGPT-User/1.0; +https://openai.com/bot.not documented
verifiable_by_rdnsOpenAI does not publish a reverse-DNS verification method for ChatGPT-User.Google does not publish a reverse-DNS verification method for Google-Extended.
what_it_controlsnot documentedGoogle-Extended controls AI training and grounding in Google systems and does not control Google Search inclusion.

Sources