IPv6 Expansion & Compression Tool

IPv6 addresses are 128 bits long, written as eight groups of four hexadecimal digits separated by colons. Example: 2001:0db8:0000:0000:0000:0000:0000:0001. To shorten, leading zeros in each group can be omitted, and the longest run of zero groups can be replaced with '::'.

The compressed form 2001:db8::1 is equivalent. Only one '::' is allowed per address. This tool expands compressed IPv6 to full form and compresses full IPv6 to the shortest valid representation.

IPv6 addresses fall into several types based on their prefix. Link-local (fe80::/10) addresses are used on a single network segment. Global unicast (2000::/3) addresses are routable on the internet. Unique local (fc00::/7) are like private IPv4. Multicast (ff00::/8) targets multiple hosts. Loopback is ::1. This tool detects and displays the address type from the prefix.

Use expansion when debugging, configuring systems that require full notation, or comparing addresses. Use compression when writing documentation, configuring routers, or keeping configs readable. Many systems accept both forms, but some legacy tools expect one or the other. This tool handles both directions instantly.