IPv6 Calculator

Expand addresses and calculate IPv6 subnets.

IPv6 address

Prefix length /64

What Is a IPv6 Calculator?

The IPv6 Calculator expands a compressed IPv6 address to its full form and computes subnet information for a chosen prefix length, including the network base address, the last address in the subnet, and the number of addresses it contains.

How to Use This IPv6 Calculator

1
Enter an addressType an IPv6 address, optionally compressed.
2
Set the prefixAdjust the prefix length slider.
3
Read the subnetReview the expanded address, network base, and last address.

Frequently Asked Questions

The double colon '::' compresses one or more consecutive groups of zeros in an IPv6 address. It can only appear once per address.

IPv6 uses 128-bit addresses, so even modest prefixes contain astronomically large numbers of addresses. A /64, for example, holds 2^64 addresses.

Yes. The tool shows the fully expanded address without compression, which is useful for documentation and analysis.

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