Classless Inter-Domain Routing (CIDR) Tools

Everything about this Classless Inter-Domain Routing address block

Base information

Address Block 2001::/32
First address 2001::
Last address 2001:0:ffff:ffff:ffff:ffff:ffff:ffff
Hosts in range 79 228 162 514 264 337 593 543 950 336
Mask bits 32

IANA Special-Purpose Registry

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

Address Block 2001::/32
Purpose TEREDO
Allocation Date January 2006
Termination Date N/A
Source true
Destination true
Forwardable true
Globally Reachable N/A
Reserved by protocol false
Defined in RFC [RFC4380] [RFC8190]
  • See Section 5 of [RFC4380] for details.


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CIDR information and calculator

Analyze a CIDR

Example: or 2001:db8::/32