Rattlesnakes By Mail

Googlebot vs GPTBot

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

How many of the compared fields have the same answer for both crawlers, and how many differ.

Googlebot and GPTBot, fields comparedGooglebot and GPTBot, fields compared. Different is the largest with 8 fields, out of 11 fields in total.Same: 3 fieldsSame3Different: 8 fieldsDifferent8
Googlebot and GPTBot, fields compared. Different is the largest with 8 fields, out of 11 fields in total. Source: each vendor's own crawler documentation, quoted and dated on every claim page.
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