IPv6 Subnet Planner

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Enter the parent network IPv6 address for subnet planning, for example 2001:db8::
Select the CIDR prefix for the parent network

Quick Templates - Load a Pre-configured Site Layout:

Subnet Allocations

Label CIDR Network Address Size (IPs) VLAN Description Color Actions

Special Addresses

::1/128
Loopback address (localhost)
RFC 4291 - Equivalent to IPv4 127.0.0.1
::/128
Unspecified address
RFC 4291 - Used when no address available
::ffff:0:0/96
IPv4-mapped IPv6 addresses
RFC 4291 - Hybrid dual-stack environments

Link-Local & Unique Local

fe80::/10
Link-local addresses
RFC 4291 - Valid only on local subnet
fc00::/7
Unique Local Addresses (ULA)
RFC 4193 - Private IPv6 addresses
fd00::/8
ULA with locally assigned prefix
RFC 4193 - Most common ULA implementation

Multicast

ff00::/8
All multicast addresses
RFC 4291 - Various scopes defined
ff02::1
All nodes (link-local scope)
RFC 4291 - Equivalent to broadcast
ff02::2
All routers (link-local scope)
RFC 4291 - Router discovery

Documentation & Global

2001:db8::/32
Documentation prefix
RFC 3849 - Examples and documentation only
2000::/3
Global Unicast Addresses
RFC 4291 - Routable public IPv6 addresses

Common Allocations

/48
Standard site allocation
RFC 6177 - 65,536 /64 subnets available
/56
Small site allocation
RFC 6177 - 256 /64 subnets available
/64
Standard LAN subnet size
RFC 4291 - Required for SLAAC