| Prefix Length | Number of Addresses | Equivalent Subnet | Typical Usage |
|---|---|---|---|
| /32 | 296 | 65,536 /48 networks | ISP Assigned to Organization |
| /48 | 280 | 65,536 /64 networks | Single Organization or Site |
| /56 | 272 | 256 /64 networks | Small Organization or Home |
| /64 | 264 | 18,446,744,073,709,551,616 | Single Subnet (Recommended) |
| /80 | 248 | 281,474,976,710,656 | Special Purpose |
| /96 | 232 | 4,294,967,296 | Special Purpose |
| /112 | 216 | 65,536 | Point-to-Point Link |
| /128 | 1 | Single Host | Loopback/Host Route |
| Address/Range | Description | Actions |
|---|---|---|
| ::1/128 | Loopback Address | |
| ::/128 | Unspecified Address | |
| fe80::/10 | Link-Local Address | |
| fc00::/7 | Unique Local Address (ULA) | |
| ff00::/8 | Multicast Address | |
| 2001:db8::/32 | Documentation | |
| 2001::/32 | Special Purpose Addresses (IETF Protocol Assignments) | |
| 2002::/16 | 6to4 Transition Mechanism |
IPv6 AddressIt is a 128-bit address, usually represented as 8 groups of 4 hexadecimal digits separated by colons. For example: 2001:0db8:85a3:0000:0000:8a2e:0370:7334
Address compression rules: Leading zeros in each group can be omitted, and consecutive groups of zeros can be replaced with :: (only once). For example: 2001:db8:85a3::8a2e:370:7334
Prefix LengthSimilar to IPv4 CIDR, used to indicate the number of bits in the network portion. For example: 2001:db8::/32 means the first 32 bits are the network address.
Subnetting: IPv6 recommends using /64 as the standard subnet size to enable SLAAC (Stateless Address Autoconfiguration). Organizations typically receive /32 or /48 prefixes and then divide them into multiple /64 subnets.
Address types: Global unicast addresses (2000::/3), link-local addresses (fe80::/10), unique local addresses (fc00::/7), multicast addresses (ff00::/8), etc.
Reverse DNS: IPv6 uses the ip6.arpa domain for reverse DNS lookups, with each nibble (4 bits) represented by a label in reverse order.