Classless Inter-Domain Routing (CIDR) Tools

Everything about this Classless Inter-Domain Routing address block

Base information

Address Block
First address
Last address
Hosts in range 256
Mask bits 24

IANA Special-Purpose Registry

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

Address Block
Purpose Deprecated (6to4 Relay Anycast)
Allocation Date June 2001
Termination Date March 2015
Source N/A
Destination N/A
Forwardable N/A
Globally Reachable N/A
Reserved by protocol N/A
Defined in RFC [RFC7526]


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CIDR information and calculator

Analyze a CIDR

Example: or 2001:db8::/32