Compress a full IPv6 address to its shortest RFC 5952 form and see exactly how many characters are saved.
RFC 5952 defines one canonical text form: lowercase hex, no leading zeros inside a group, and a single '::' replacing the longest zero run. Ties are resolved in favour of the leftmost run. Two spellings of the same address break string comparisons in ACLs, allow-lists and log correlation, so normalising to the canonical form removes a whole class of false negatives.
IPv6 Address Compression
Leading zeros in each group are dropped and the longest run of all-zero groups (two or more) is replaced by '::'.
Leading zeros in each group are dropped and the longest run of all-zero groups (two or more) is replaced by '::'. RFC 5952 defines one canonical text form: lowercase hex, no leading zeros inside a group, and a single '::' replacing the longest zero run. Ties are resolved in favour of the leftmost run.
Two spellings of the same address break string comparisons in ACLs, allow-lists and log correlation, so normalising to the canonical form removes a whole class of false negatives.
This calculator takes 1 input: IPv6 address. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.