Meta
facebookexternalhit
About this crawler
Meta crawler used for shared link previews on Facebook, Instagram, and Messenger.
Usually means: The request looks like AI-related crawler traffic, but it does not fit neatly into answer, index, or training traffic.
User agent
facebookexternalhitDataFast matches these as user-agent tokens, not full browser strings. Providers may add surrounding version or product text.
IP verification
Verified when user agent and IP range both match
DataFast first matches the crawler user-agent token, then compares the request IP with published ranges from the crawler operator when those ranges exist.
User agent
Request user agent contains facebookexternalhit.
Request IP
Server-side tracking forwards the crawler IP seen by your backend.
Range check
The IP is compared with published CIDR ranges or JSON range endpoints.
Sample IP ranges
157.240.14.0/2431.13.73.0/242a03:2880:f235::/482a03:2880:f048::/482a03:2880:f24d::/482a03:2880:f134::/482a03:2880:f352::/482a03:2880:f23a::/482a03:2880:ff10::/472a03:2880:f329::/48Showing up to 10 ranges from the configured official sources.
Discover when bots and AI assistants crawl your website.
Install the server-side tracker to see which AI assistants, search engines, and training crawlers request your pages. It helps you understand what bots are trying to find, including pages that return 404.