Typically, IPv6 subnets use a prefix length of what size?

In IPv6 addressing, a subnet typically uses a prefix length of /64, which is considered the standard size for most subnets. The /64 prefix length indicates that the first 64 bits of the address are used for the network portion, while the remaining 64 bits are reserved for host addresses within that subnet.

This /64 subnet size is important because it allows for a vast number of individual addresses—over 18 quintillion (18,446,744,073,709,551,616) unique addresses—sufficient for most networks. The design of IPv6 accounts for this large address space to accommodate a wide variety of devices, from traditional computers to IoT devices.

The significance of the /64 prefix is further emphasized by the fact that many IPv6-enabled technologies and environments, such as Stateless Address Autoconfiguration (SLAAC), are designed to work effectively with /64 subnets. Using this size, devices can automatically configure their IPv6 addresses without the need for a dedicated DHCP server.

While other prefix lengths like /32, /48, and /128 are used in specific scenarios—such as for multi-site organizations or loopback interfaces—they are not the standard for typical subnets. A /32 is typically assigned