Rattlesnakes By Mail

Googlebot vs GPTBot

Googlebot and GPTBot compared on 11 documented fields, from 18 claims, last verified 2026-09-15.

FieldGooglebotGPTBotComparison
cites_sourcesyesnot documenteddifferent
honours_crawl_delaynonot_documenteddifferent
observed_verified_request_ratio_census0.991not documenteddifferent
publishes_ip_listyesyessame
purpose_documentedsearchtrainingdifferent
reads_llms_txtnonot documenteddifferent
respects_robots_txtyesyessame
robots_txt_fetch_markernot documentedyesdifferent
separate_search_and_training_tokensyesyessame
user_agent_string_fullMozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html)Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko); compatible; GPTBot/1.4; +https://openai.com/gptbotdifferent
verifiable_by_rdnsyesnot_documenteddifferent

Differences

FieldGooglebot statementGPTBot statement
cites_sourcesGoogle AI Overviews and AI Mode return AI generated responses with links to supporting websites.not documented
honours_crawl_delayGoogle does not support the robots.txt Crawl-delay directive for Googlebot.OpenAI does not publish whether GPTBot honours the robots.txt Crawl-delay directive.
observed_verified_request_ratio_censusGooglebot requests to Rattlesnakes By Mail matched Google's published IP ranges on 108 of 109 requests between 2026-09-13T20:00Z and 2026-09-15T09:00Z. Googlebot's first request to Rattlesnakes By Mail in that window was /robots.txt at 2026-09-14T11:53:00Z.not documented
purpose_documentedGooglebot crawls pages for Google Search, Google Images, Google Video, Google News, and Discover.GPTBot crawls content that may be used to train OpenAI generative AI foundation models.
reads_llms_txtGoogle Search does not use llms.txt files.not documented
robots_txt_fetch_markernot documentedOpenAI may add a robots.txt marker to the GPTBot user agent string when GPTBot fetches robots.txt files.
user_agent_string_fullGooglebot sends the user agent string Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html).GPTBot sends the user agent string Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko); compatible; GPTBot/1.4; +https://openai.com/gptbot.
verifiable_by_rdnsGooglebot requests are verifiable by reverse DNS lookup resolving to googlebot.com, google.com, or googleusercontent.com.OpenAI does not publish a reverse-DNS verification method for GPTBot.

Sources