You need to inspect the routed prefix behind a public IP before moving to RPKI or path analysis.
BGP Prefix Lookup
Inspect visible BGP prefix context for a public IP or routed prefix.
Use BGP Prefix Lookup to see the routed prefix, visible origin ASN context, and nearby less-specific or more-specific routes so you can understand what public BGP is actually showing before moving to deeper routing or authorization checks.
Check visible prefix context before assuming a public IP belongs to the route you expected.
Lookup result
8.8.8.8
ANNOUNCED
Prefix details
Field Value Source
Visible origins
ASN Name Context
No visible origin ASN data was returned.
Less-specific routes
Prefix Origin Context
No less-specific routes were returned.
More-specific routes
Prefix Origin Context
No more-specific routes were returned.
When to use this tool
A prefix appears to originate from the wrong network and you want to confirm the visible BGP context first.
You are comparing announcements, ownership, or visibility for a routed prefix.
An IP address belongs to an expected provider, but the live prefix context still looks wrong.
You want to see less-specific or more-specific route context before deeper investigation.
You need a quick prefix-level check before ASN Lookup, RPKI ROA, or Traceroute.
How to interpret results
Prefix announced
The routing dataset shows the entered prefix or its encompassing route as currently announced.
Unexpected origin ASN
The visible origin does not match the provider or ASN you expected.
Less-specific route context
Broader parent routes are visible alongside the entered resource.
More-specific route context
More-specific routes may exist below the entered resource.
No public route data
The entered IP or prefix did not return usable public BGP context.
Common issues this tool helps uncover
The visible origin ASN differs from the expected operator
The routed prefix is broader or narrower than expected
A public IP resolves into a prefix with surprising ownership or visibility
Less-specific parent routes change how the prefix should be interpreted
The prefix is announced, but route-origin authorization still needs an RPKI check
The resource is not visible enough in public BGP data to confirm the expected route
Next steps
Run ASN Lookup
Move to ASN Lookup if you need deeper operator and ownership context for the visible origin.
Run ASN LookupRun RPKI ROA Check
Validate whether the visible prefix and origin ASN are authorized.
Run RPKI ROA CheckCheck IP Lookup
If you started with an IP address, compare the BGP view with IP owner and reverse-DNS context.
Check IP LookupRun Traceroute
If the prefix looks correct but traffic still fails, inspect the network path next.
Run TracerouteRelated tools
ASN Lookup
Look up AS numbers, prefixes, and operator ownership details.
RPKI ROA Check
Validate origin authorization for routes and announced prefixes.
IP Lookup
Inspect basic ownership, reverse DNS, and network details for an IP.
Traceroute
Trace the network path between a client and destination host.
Subnet Calculator
Calculate network ranges, masks, and host counts from CIDR blocks.
BGP Prefix Lookup FAQ
What does BGP Prefix Lookup do?
It checks public BGP routing data for a public IP or prefix and shows the visible routed prefix, origin ASN context, visibility, and related less-specific or more-specific routes.
What input should I enter?
Enter a public IP address or routed prefix such as 8.8.8.8 or 8.8.8.0/24.
Why is the prefix different from the IP I entered?
Public routing data often maps an IP address to its encompassing announced prefix, which is the unit BGP actually advertises.
Does this prove the route is authorized?
No. BGP Prefix Lookup shows visible route context. Route-origin authorization still needs RPKI ROA Check.
What should I check after this tool?
Usually ASN Lookup, RPKI ROA Check, IP Lookup, or Traceroute depending on whether the problem is ownership, authorization, or path related.