Networking & IT Tools

IPv6 Compressor / Expander

Enter an IPv6 address in either compressed or expanded form to see both notations side by side.

Expanded (full form)
2001:0db8:0000:0000:0000:ff00:0042:8329
Compressed (shorthand)
2001:db8::ff00:42:8329

Compression replaces the longest run of consecutive all-zero groups with "::" (used at most once, per RFC 5952) and drops leading zeros within each remaining group.

How to use this tool

  1. 1Enter an IPv6 address (compressed or expanded).
  2. 2See the fully expanded 8-group form.
  3. 3See the shortest valid compressed form.

Frequently asked questions

What does "::" mean in an IPv6 address?+

It's shorthand for one or more consecutive groups of all zeros, and can only be used once per address (per RFC 5952).

Can I enter an address with an embedded IPv4 part?+

Yes — addresses like ::ffff:192.168.1.1 (used for IPv4-mapped IPv6) are supported.

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