How the IPv6 prefix is calculated
The prefix length identifies the leading network bits. The calculator masks the remaining bits to find the first address, then computes the final address and total size of that prefix.
Compressed IPv6 notation
The double colon can replace one run of zero groups and may appear only once. The result is shown in lowercase canonical form, with the longest zero run compressed.
IPv6 address behavior
IPv6 does not use broadcast addresses. Multicast and Neighbor Discovery serve different roles. Before using a prefix, check it against your local routes, VLANs, VPNs and upstream allocation. This tool performs arithmetic only.