AnkhKit

IPv6 ULA Generator (RFC 4193)

Runs 100% in your browser — your files never leave your device.

Unique local addresses are the IPv6 equivalent of private ranges: routable inside your network, useless outside it. Enter a MAC address and this tool applies the first RFC 4193 method — timestamp plus MAC, SHA-1 hashed, low 40 bits — to mint your fd00::/48 block along with the first and last routable /64 subnets.

How it works

  1. 1

    Enter a MAC address

    Any device MAC seeds the generator.

  2. 2

    Generate the block

    Timestamp plus MAC are hashed per RFC 4193.

  3. 3

    Copy your /48

    Take the ULA block and its first and last routable subnets.

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