Classless Inter-Domain Routing (CIDR) Tools

Everything about this Classless Inter-Domain Routing address block

Base information

Address Block 2001:20::/28
First address 2001:20::
Last address 2001:2f:ffff:ffff:ffff:ffff:ffff:ffff
Hosts in range 1 267 650 600 228 229 401 496 703 205 376
Mask bits 28

IANA Special-Purpose Registry

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

Address Block 2001:20::/28
Purpose ORCHIDv2
Allocation Date July 2014
Termination Date N/A
Source true
Destination true
Forwardable true
Globally Reachable true
Reserved by protocol false
Defined in RFC [RFC7343]


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CIDR information and calculator

Analyze a CIDR

Example: or 2001:db8::/32