What it does
Enter an IPv6 address with a prefix length (e.g. 2001:db8::/32) and get the expanded network address, the first and last address in the block, and the total number of addresses it contains.
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How it works
- The IPv6 address is expanded to its full 128-bit representation (handling the
::zero-compression shorthand). - The prefix length defines how many of the leading bits are fixed (network bits); the rest are host bits.
- The network (first) address is the input address with all host bits cleared to
0; the last address has all host bits set to1. - The total address count is
2^(128 - prefix), shown using scientific notation for very large ranges since it can vastly exceed what JavaScript numbers can represent precisely.
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