IPv6 notation tool

Expand IPv6 address fd1b:feb0:9171:8749:7a9a:18ff:fea0:99a5

Write any valid IPv6 address in its complete eight-group form for subnetting, binary analysis, logs, and documentation.

Example: 2001:db8::1

The conversion runs locally and does not use an external lookup service.

Expansion result

Full IPv6 notation for fd1b:feb0:9171:8749:7a9a:18ff:fea0:99a5

Expanded IPv6 address

fd1b:feb0:9171:8749:7a9a:18ff:fea0:99a5

Compressed IPv6

fd1b:feb0:9171:8749:7a9a:18ff:fea0:99a5

Expanded IPv6

fd1b:feb0:9171:8749:7a9a:18ff:fea0:99a5

IPv6 groups

8 groups of 4 hexadecimal digits

Address size

128 bits

Expansion rules

How IPv6 expansion works

  1. 1An IPv6 address always has eight 16-bit hexadecimal groups.
  2. 2Each visible group is left-padded with zeroes until it contains four digits.
  3. 3If :: appears, it is replaced with the number of 0000 groups needed to reach eight groups.

Binary representation

128 bits, grouped for inspection

Each block below represents one 16-bit IPv6 group. This form is useful when comparing prefix bits or troubleshooting subnet boundaries.

1111110100011011 1111111010110000 1001000101110001 1000011101001001 0111101010011010 0001100011111111 1111111010100000 1001100110100101
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