IPv6 Compression
Shorten IPv6 addresses into canonical notation.
IPv6 addresses can be written compactly by dropping leading zeros in each group and replacing the longest run of all-zero groups with a double colon. RFC 5952 defines one canonical form so the same address is always written the same way.
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How IPv6 Compression works
What it does
Shorten IPv6 addresses into canonical notation.
What you get
A shortened, canonical IPv6 address.
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What if a check cannot finish?
Confirm your input and try again. A timeout, blocked request, or unavailable provider is not proof that a domain is broken. Internet measurements and third-party services have limits.
IPv6 Compression — frequently asked questions
Can I use the double colon more than once?
No. With two, there would be no way to tell how many zero groups each stands for. Exactly one per address.
Which run of zeros gets collapsed?
The longest one. If two runs are the same length, the leftmost is collapsed — that rule is what makes the canonical form unique.
Is the compressed address the same address?
Identical. Compression is purely notation; the underlying 128 bits do not change.