# Google-Extended vs Perplexity-User

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

| Field | Google-Extended | Perplexity-User | Comparison |
| --- | --- | --- | --- |
| cites_sources | not documented | yes | different |
| honours_crawl_delay | n/a | not_documented | different |
| publishes_ip_list | no | yes | different |
| purpose_documented | policy_only | user_fetch | different |
| reads_llms_txt | not documented | not_documented | different |
| respects_robots_txt | n/a | no | different |
| robots_token_differs_from_ua | yes | not documented | different |
| separate_search_and_training_tokens | yes | not_documented | different |
| user_agent_string_full | not documented | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Perplexity-User/1.0; +https://perplexity.ai/perplexity-user) | different |
| verifiable_by_rdns | n/a | not_documented | different |
| what_it_controls | Gemini model training and grounding, not Search inclusion | not documented | different |

## Differences

| Field | Google-Extended statement | Perplexity-User statement |
| --- | --- | --- |
| cites_sources | not documented | Perplexity includes a link to each page that Perplexity-User visits in the Perplexity response. |
| honours_crawl_delay | Google does not publish any Crawl-delay behaviour for the Google-Extended token. | Perplexity does not publish whether Perplexity-User honours the robots.txt Crawl-delay directive. |
| publishes_ip_list | Google 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 Perplexity-User as a JSON file at https://www.perplexity.ai/perplexity-user.json. |
| purpose_documented | Google-Extended is a standalone product token that controls whether Google uses crawled content to train Gemini models. | Perplexity-User visits web pages to answer questions that users ask Perplexity. |
| reads_llms_txt | not documented | Perplexity does not publish whether Perplexity-User reads llms.txt files. |
| respects_robots_txt | Google-Extended is a robots.txt token that publishers set to control use of crawled content for Gemini training. | Perplexity-User ignores robots.txt rules because a user requests each Perplexity-User fetch. |
| robots_token_differs_from_ua | Google-Extended is a robots.txt control token and does not correspond to a crawler user agent string. | not documented |
| separate_search_and_training_tokens | Google-Extended controls Gemini training use only and does not affect inclusion in Google Search. | Perplexity does not document Perplexity-User as a search or training opt-out token. |
| user_agent_string_full | not documented | Perplexity-User sends the user agent string Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Perplexity-User/1.0; +https://perplexity.ai/perplexity-user). |
| verifiable_by_rdns | Google does not publish a reverse-DNS verification method for Google-Extended. | Perplexity does not publish a reverse-DNS verification method for Perplexity-User. |
| what_it_controls | Google-Extended controls AI training and grounding in Google systems and does not control Google Search inclusion. | not documented |

## Sources

- https://developers.google.com/search/docs/appearance/ai-features
- https://developers.google.com/search/docs/crawling-indexing/google-common-crawlers
- https://docs.perplexity.ai/docs/resources/perplexity-crawlers
- https://www.perplexity.ai/perplexity-user.json