IPv4 Scope & Special-Use Lookup
Classify an IPv4 address or block against the IANA special-purpose registry: private, CGNAT, loopback, documentation, multicast, reserved, or globally reachable.
This tool handles input and primary processing in your browser and is designed not to send the input to QuickKit’s server.
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How it works
Matches the input (address or CIDR; bare addresses are /32) against a complete snapshot of IANA's IPv4 Special-Purpose Address Space registry (Last Updated 2025-10-09), plus the multicast block 224.0.0.0/4, which that registry does not cover. The most specific block containing the whole input decides the primary scope, so 192.0.0.9/32 wins over 192.0.0.0/24. "Globally reachable" is read from the registry's own column rather than inferred from the fact that an entry exists — AS112, AMT, PCP and TURN anycast blocks are registry entries that are globally reachable. "Unspecified" means the registry states no value (a terminated row, or the multicast block, which is outside this registry). "Mixed" means different parts of the input resolve differently. The legacy class is historical context only: classful addressing was superseded by CIDR in 1993 and the current specification is RFC 4632 (BCP 122), so the class does not determine any prefix length today.