Classless Inter-Domain Routing (CIDR) Tools

Everything about this Classless Inter-Domain Routing address block

Base information

Address Block ::/128
First address ::
Last address ::
Hosts in range 1
Mask bits 128

IANA Special-Purpose Registry

This CIDR is in a special-purpose block reserved by IANA for special purposes.

Address Block ::
Purpose Loopback Address
Allocation Date February 2006
Termination Date N/A
Source false
Destination false
Forwardable false
Globally Reachable false
Reserved by protocol true
Defined in RFC [RFC4291]


REST API on request


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CIDR information and calculator

Analyze a CIDR

Example: or 2001:db8::/32