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Google-Extended vs PerplexityBot

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

FieldGoogle-ExtendedPerplexityBotComparison
cites_sourcesnot documentedyesdifferent
honours_crawl_delayn/anot_documenteddifferent
publishes_ip_listnoyesdifferent
purpose_documentedpolicy_onlysearchdifferent
reads_llms_txtnot documentednot_documenteddifferent
respects_robots_txtn/ayesdifferent
robots_token_differs_from_uayesnot documenteddifferent
separate_search_and_training_tokensyesnot_documenteddifferent
user_agent_string_fullnot documentedMozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; PerplexityBot/1.0; +https://perplexity.ai/perplexitybot)different
verifiable_by_rdnsn/anot_documenteddifferent
what_it_controlsGemini model training and grounding, not Search inclusionnot documenteddifferent

Differences

FieldGoogle-Extended statementPerplexityBot statement
cites_sourcesnot documentedPerplexity links to the websites that PerplexityBot surfaces in Perplexity search results.
honours_crawl_delayGoogle does not publish any Crawl-delay behaviour for the Google-Extended token.Perplexity does not publish whether PerplexityBot honours the robots.txt Crawl-delay directive.
publishes_ip_listGoogle publishes no IP list for Google-Extended because Google-Extended has no separate HTTP request user agent string.Perplexity publishes the IP address ranges used by PerplexityBot as a JSON file at https://www.perplexity.ai/perplexitybot.json.
purpose_documentedGoogle-Extended is a standalone product token that controls whether Google uses crawled content to train Gemini models.PerplexityBot surfaces and links websites in Perplexity search results.
reads_llms_txtnot documentedPerplexity does not publish whether PerplexityBot reads llms.txt files.
respects_robots_txtGoogle-Extended is a robots.txt token that publishers set to control use of crawled content for Gemini training.PerplexityBot honours robots.txt rules that webmasters set for the PerplexityBot token.
robots_token_differs_from_uaGoogle-Extended is a robots.txt control token and does not correspond to a crawler user agent string.not documented
separate_search_and_training_tokensGoogle-Extended controls Gemini training use only and does not affect inclusion in Google Search.Perplexity does not document a separate training crawler token alongside PerplexityBot.
user_agent_string_fullnot documentedPerplexityBot sends the user agent string Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; PerplexityBot/1.0; +https://perplexity.ai/perplexitybot).
verifiable_by_rdnsGoogle does not publish a reverse-DNS verification method for Google-Extended.Perplexity does not publish a reverse-DNS verification method for PerplexityBot.
what_it_controlsGoogle-Extended controls AI training and grounding in Google systems and does not control Google Search inclusion.not documented

Sources