Classless Inter-Domain Routing (CIDR) Tools

Everything about this Classless Inter-Domain Routing address block

Base information

Address Block fc00::/7
First address fc00::
Last address fdff:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Hosts in range 2 658 455 991 569 831 745 807 614 120 560 689 152
Mask bits 7

IANA Special-Purpose Registry

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

Address Block fc00::/7
Purpose Unique-Local
Allocation Date October 2005
Termination Date N/A
Source true
Destination true
Forwardable true
Globally Reachable false
Reserved by protocol false
Defined in RFC [RFC4193] [RFC8190]
  • See [RFC4193] for more details on the routability of Unique-Local addresses. The Unique-Local prefix is drawn from the IPv6 Global Unicast Address range, but is specified as not globally routed.


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