IPv6 calculator

Subnet details, /127 and /128 planning, splitting, compress/expand, overlap check.

What it is for

Convert IPv6 between compressed and expanded forms.

Why it helps

One canonical form in configs and lists — fewer mistakes when comparing or searching addresses.

Compress / expand

Result

Compressed2001:db8:1:ffff::a
Expanded2001:0db8:0001:ffff:0000:0000:0000:000a