Social preview fetcher · Google
Google Messages user agent, IP ranges and robots.txt
Google Messages is Google's social preview fetcher. It identifies itself with the GoogleMessages user-agent token, does not consult robots.txt according to its operator, and runs from 496 published IP prefixes.
- Operator
- Reviewed
- September 2026
- Sources
- 2
- Operator
- User-agent token
- GoogleMessages
- Purpose
- Social preview fetcher
- robots.txt token
- undocumented
- Honors robots.txt
- No, per the operator
- Published IP ranges
- Yes, 496 prefixes (248 IPv4, 248 IPv6)
- Verification
- Reverse DNS with matching forward DNS, or match the source IP against user-triggered-fetchers.json or user-triggered-fetchers-google.json.
- Reverse DNS suffix
- gae.googleusercontent.com (***-***-***-***.gae.googleusercontent.com) or google.com (google-proxy-***-***-***-***.google.com)
- Full user-agent example
- GoogleMessages
Block or allow Google Messages in robots.txt
User-agent: undocumented
Disallow: /User-agent: undocumented
Allow: /Verify a request is really Google Messages
Anyone can put GoogleMessages in a User-Agent header. Reverse DNS with matching forward DNS, or match the source IP against user-triggered-fetchers.json or user-triggered-fetchers-google.json.
host <request-ip>
# expect a hostname ending in gae.googleusercontent.com (***-***-***-***.gae.googleusercontent.com) or google.com (google-proxy-***-***-***-***.google.com)
host <that-hostname>
# expect it to resolve back to <request-ip>Published IP ranges
Google publishes a machine-readable list. Our probe read it on 2026-09-06; the file's own creation time was 2026-09-04.
- Prefixes
- 496
- IPv4
- 248
- IPv6
- 248
First entries at fetch time: 2001:4860:4801:4004::/64, 2001:4860:4801:4008::/64, 2001:4860:4801:4009::/64
SHA-256 of the fetched body: 5590a1a5d2fbe83872191aa2d8d45e9c854c56c49b742df9d33b7612f5482a5a
What Google Messages does
Google operates the Google Messages fetcher, which generates link previews for URLs sent in chat messages. It is a user-triggered fetcher and generally ignores robots.txt; Google documents no robots.txt token for it. Site owners verify requests by reverse DNS to a gae.googleusercontent.com or google.com hostname with a matching forward lookup, or against Google's published user-triggered-fetchers JSON files.
In logs the request carries the bare user-agent string GoogleMessages with no version number or product URL. Google groups it with its user-triggered fetchers. A person sends a URL in a chat message, and the fetcher retrieves the page to build the link preview shown in the conversation. Google added this fetcher to its crawler documentation on 2026-01-21 according to the changelog. The entry records no statement from Google about JavaScript execution or request volume for this fetcher, so both remain undocumented.
Because each fetch follows a user action, Google says the fetcher generally ignores robots.txt, and no robots.txt token is documented. Allowing it means links to your pages show a preview inside Google Messages chats; blocking it at the server level removes that preview. Google's purpose statement mentions only link previews, with no reference to search indexing or AI training, so the documented effect of a block is limited to those previews.
To confirm a request is genuine, reverse-resolve the IP and expect a hostname of the form ***-***-***-***.gae.googleusercontent.com or google-proxy-***-***-***-***.google.com, then forward-resolve that hostname and check the IP matches. Google also publishes user-triggered-fetchers.json and user-triggered-fetchers-google.json for IP matching; the google variant is the range file this entry points to. A request from an address outside those ranges that fails the DNS check is not the documented fetcher.
Operator note. User-triggered fetcher; generally ignores robots.txt. Added to the docs on 2026-01-21 per the changelog.
Common questions
- Should I block Google Messages?
- Blocking it stops link previews from appearing when someone shares your URL in a Google Messages chat. Google documents no connection between this fetcher and search ranking or indexing, so the only documented effect is on those previews. Since it generally ignores robots.txt, any block would need to be applied by user-agent or IP at the server.
- Does Google Messages respect robots.txt?
- Generally not. Google classifies it as a user-triggered fetcher and states that these fetchers generally ignore robots.txt because the request follows a user action. Google lists no robots.txt token for GoogleMessages, so there is no directive to write for it.
- How do I verify the Google Messages fetcher?
- Do a reverse DNS lookup on the IP and expect a hostname under gae.googleusercontent.com or a google-proxy hostname under google.com, then a forward lookup that returns the same IP. Or match the IP against Google's user-triggered-fetchers-google.json or user-triggered-fetchers.json range files.
Sources
The operator documentation used for this entry. Recorded review date September 2026; consult the linked pages for current policy and compare them with this dated snapshot.
This registry documents how operators describe their own bots so site owners can identify and control them. It does not publish third-party IP lists or guess at undocumented behaviour. To see how your own site responds to automated visitors, the bot detection scanner reads a URL's live response and names the protection it finds.