IPv6 Subnet Calculator

Calculate IPv6 subnet ranges from a given prefix.

Calculator Inputs

Results

Enter a valid IPv6 prefix to calculate subnets.

IPv6 Subnetting Made Simple

This calculator helps you determine the number of subnets you can create from a given IPv6 address block. Enter your assigned prefix (e.g., a /48 from your ISP) and the new, longer prefix length you want to use for your subnets (e.g., /64 for your LANs). The tool will calculate how many subnets this creates.

Frequently Asked Questions

Why subnet IPv6?

Even though IPv6 provides an enormous address space, subnetting is still crucial for network organization, security, and traffic management. It allows you to segment a large address block into smaller, manageable networks for different departments, services, or locations.

What is a typical subnet size in IPv6?

The standard and most common subnet size for a LAN is a /64. This provides 2^64 addresses, which is more than enough for virtually any local network, and it is required for features like SLAAC (Stateless Address Autoconfiguration).