IPv6 ULA Generator
Generate a random RFC 4193 unique local address prefix for a private IPv6 network.
Runs entirely in your browser.
Generate a Unique Local IPv6 Address Prefix
About IPv6 ULA Generator
A unique local address is IPv6's equivalent of a private IPv4 range: routable inside your own network, never on the public internet. RFC 4193 reserves fd00::/8 for prefixes you assign yourself, followed by a random 40-bit global ID.
Random is the point. The 40 bits exist so that two networks picking prefixes independently almost certainly will not collide, which matters the day you merge them or set up a VPN between them. Picking fd00::/48 by hand - as many people do - defeats that entirely.
Generated here with your browser's cryptographic random number generator, and never sent anywhere.
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