# Google-Extended vs Googlebot

Google-Extended and Googlebot compared on 12 documented fields, from 18 claims, last verified 2026-09-15.

| Field | Google-Extended | Googlebot | Comparison |
| --- | --- | --- | --- |
| cites_sources | not documented | yes | different |
| honours_crawl_delay | n/a | no | different |
| observed_verified_request_ratio_census | not documented | 0.991 | different |
| publishes_ip_list | no | yes | different |
| purpose_documented | policy_only | search | different |
| reads_llms_txt | not documented | no | different |
| respects_robots_txt | n/a | yes | different |
| robots_token_differs_from_ua | yes | not documented | different |
| separate_search_and_training_tokens | yes | yes | same |
| user_agent_string_full | not documented | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) | different |
| verifiable_by_rdns | n/a | yes | different |
| what_it_controls | Gemini model training and grounding, not Search inclusion | not documented | different |

## Differences

| Field | Google-Extended statement | Googlebot statement |
| --- | --- | --- |
| cites_sources | not documented | Google AI Overviews and AI Mode return AI generated responses with links to supporting websites. |
| honours_crawl_delay | Google does not publish any Crawl-delay behaviour for the Google-Extended token. | Google does not support the robots.txt Crawl-delay directive for Googlebot. |
| observed_verified_request_ratio_census | not documented | Googlebot 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. |
| publishes_ip_list | Google publishes no IP list for Google-Extended because Google-Extended has no separate HTTP request user agent string. | Google publishes the IP address ranges used by Googlebot at https://developers.google.com/static/crawling/ipranges/common-crawlers.json. |
| purpose_documented | Google-Extended is a standalone product token that controls whether Google uses crawled content to train Gemini models. | Googlebot crawls pages for Google Search, Google Images, Google Video, Google News, and Discover. |
| reads_llms_txt | not documented | Google Search does not use 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. | Googlebot obeys robots.txt rules when crawling automatically. |
| 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 |
| user_agent_string_full | not documented | Googlebot sends the user agent string Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html). |
| verifiable_by_rdns | Google does not publish a reverse-DNS verification method for Google-Extended. | Googlebot requests are verifiable by reverse DNS lookup resolving to googlebot.com, google.com, or googleusercontent.com. |
| 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/crawling/docs/crawlers-fetchers/verifying-googlebot
- https://developers.google.com/search/blog/2019/07/a-note-on-unsupported-rules-in-robotstxt
- https://developers.google.com/search/docs/appearance/ai-features
- https://developers.google.com/search/docs/crawling-indexing/google-common-crawlers
- https://developers.google.com/search/docs/fundamentals/ai-optimization-guide
- https://developers.google.com/static/crawling/ipranges/common-crawlers.json
- https://rattlesnakesbymail.com/observed/googlebot