Crawler directory · AI training crawler
Google-Extended: user agent, robots.txt rules, and how to allow or block it
Google-Extended is a robots.txt product token, not a separate crawler: Google fetches pages with its normal crawlers and uses this token to decide whether the content may be used for Gemini model training and grounding. It has no User-Agent string of its own.
- Operator
- Feeds
- Gemini apps and Vertex AI
- Type
- AI training crawler
- robots.txt token
- Google-Extended
- Fetches pages itself
- No — it is a permission token only
Google-Extended user agent
Google-Extended never makes requests, so it has no User-Agent header of its own — it exists only as a robots.txt token. The requests you see in your logs come from the vendor’s normal crawlers.
Official documentation: developers.google.com. Vendors change their crawlers, so check it for the current details.
Should you allow or block Google-Extended?
Blocking stops future crawls from being used for model training. It does not remove content already collected, and it does not stop you being cited in live answers, which use separate retrieval bots.
Heads up: Google says Google-Extended does not affect inclusion or ranking in Google Search.
robots.txt rules for Google-Extended
Put these in the robots.txt at the root of your domain.
Block Google-Extended
User-agent: Google-Extended Disallow: /
Explicitly allow Google-Extended
User-agent: Google-Extended Allow: /
Block only part of your site
User-agent: Google-Extended Disallow: /private/ Allow: /
robots.txt states your policy; it does not enforce it. A CDN or firewall can block a bot your robots.txt allows, which is why it is worth testing rather than assuming.
Check what your site does today
The free AI bot checker reads your robots.txt and tells you whether GPTBot, ClaudeBot, PerplexityBot and nine other AI crawlers are allowed, blocked or crawling by default, then runs a live GPTBot fetch to prove your content is actually served.
Check my site free →Questions, answered
What is Google-Extended?+
Google-Extended is a robots.txt product token, not a separate crawler: Google fetches pages with its normal crawlers and uses this token to decide whether the content may be used for Gemini model training and grounding. It has no User-Agent string of its own.
How do I block Google-Extended in robots.txt?+
Add these two lines to the robots.txt at the root of your domain: User-agent: Google-Extended Disallow: / User-agent tokens are matched case-insensitively. The rule applies from the crawler's next visit; it does not delete anything already collected. Google says Google-Extended does not affect inclusion or ranking in Google Search.
Will blocking Google-Extended affect my Google rankings?+
No. Google-Extended is separate from Googlebot, so blocking it does not change how Google Search indexes or ranks you. Blocking stops future crawls from being used for model training. It does not remove content already collected, and it does not stop you being cited in live answers, which use separate retrieval bots.
Related crawlers
More on the trade-offs in the AI bot policies guide and the robots.txt guide.