facebookexternalhit
Run by Meta
How to detect facebookexternalhit
facebookexternalhit names itself in its user agent, but anyone can copy a user agent, so it is detected by confirming the user agent against other signals: source IP confirmed as the operator's own network; and how the session clicks, types, moves and navigates matches an automated agent.
- Detection method
- Self-declaredThe agent names itself in its user agent, and Verisoul confirms it with network, device or behavioral data. A user agent alone is never enough.
- Signals that identify it
- NetworkSource IP confirmed as the operator's own network
- DeviceNames itself as facebookexternalhit in its user agent, which we check against the rest of the session
- BehavioralHow the session clicks, types, moves and navigates matches an automated agent
Every signal Verisoul checks for facebookexternalhit
facebookexternalhit names itself in its user agent. Anyone can copy that, so we only label a session facebookexternalhit when the other signals check out too.
- Not used
Cryptographic
Not needed to identify it
- Used
Network
Source IP confirmed as the operator's own network
- Used
Device
Names itself as facebookexternalhit in its user agent, which we check against the rest of the session
- Used
Behavioral
How the session clicks, types, moves and navigates matches an automated agent
How often you'll see it
Very common
About 6% of global crawler traffic in September 2026, per Cloudflare Radar
More from Meta
- Meta-ExternalAgentMeta's crawler that collects public pages for AI training.Self-declaredHow common: Very common
- Meta-ExternalAdsChecks ad landing pages for Meta's ad products.Self-declaredHow common: Uncommon
- Meta-ExternalFetcherFetches a page when a person asks Meta AI about it.Self-declaredHow common: Uncommon
- Meta-WebIndexerMeta's crawler that indexes pages for Meta AI search answers.Self-declaredHow common: Uncommon
- Meta MuseMeta's autonomous personal AI agent, which carries out multi-step tasks on the web for a person.InferredHow common: Growing
- Meta-ExternalTestAn AI agent from Meta that works in a browser and signs its requests.SignedHow common: Very uncommon
Questions about facebookexternalhit
How do you detect facebookexternalhit?
facebookexternalhit names itself in its user agent, but anyone can copy a user agent, so it is detected by confirming the user agent against other signals: source IP confirmed as the operator's own network; and how the session clicks, types, moves and navigates matches an automated agent.
What is facebookexternalhit?
facebookexternalhit is Builds the link preview when someone shares a URL on Facebook, Instagram or Messenger.
Does facebookexternalhit identify itself?
Partly. facebookexternalhit names itself in its user agent, but user agents are easy to copy, so the name alone is not proof.
Can a bot pretend to be facebookexternalhit?
A bot can copy facebookexternalhit's user agent or markers, but the network, device and behavior signals will not match, so it is not labeled facebookexternalhit.
How common is facebookexternalhit?
Very common. About 6% of global crawler traffic in September 2026, per Cloudflare Radar.
What does the Verisoul API return for facebookexternalhit?
Every session Verisoul identifies as facebookexternalhit carries an agent block with id "facebookexternalhit", name, provider, type "other", detection_method "self_declared" and the detection_signals used (network, behavioral). Build rules on the id, type and detection method.