IPv6 notation tool

Expand IPv6 address 2001:1890:fcfe:a3:726:2:5a:5d4b

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 2001:1890:fcfe:a3:726:2:5a:5d4b

Expanded IPv6 address

2001:1890:fcfe:00a3:0726:0002:005a:5d4b

Compressed IPv6

2001:1890:fcfe:a3:726:2:5a:5d4b

Expanded IPv6

2001:1890:fcfe:00a3:0726:0002:005a:5d4b

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.

0010000000000001 0001100010010000 1111110011111110 0000000010100011 0000011100100110 0000000000000010 0000000001011010 0101110101001011
Compress this IPv6 address

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