Local IPv6 Generator
Generate a random unique local IPv6 prefix.
Unique local addresses are IPv6's private range, equivalent in purpose to 10.0.0.0/8 in IPv4. RFC 4193 asks you to pick the 40 bits after fd at random so two networks are unlikely to collide if they are ever joined — this generates such a /48.
Your input
Private, browser-based processingResults
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How Local IPv6 Generator works
What it does
Generate a random unique local IPv6 prefix.
What you get
A random unique local /48 IPv6 prefix.
On your device
Your input is processed in this browser. Copy or download the result when you are ready.
What if a check cannot finish?
Confirm your input and try again. A timeout, blocked request, or unavailable provider is not proof that a domain is broken. Internet measurements and third-party services have limits.
Local IPv6 Generator — frequently asked questions
Why does the prefix have to be random?
So that merging two private networks later does not create overlapping addresses. Everyone defaulting to the same prefix is exactly the collision the randomness avoids.
Are these addresses routable on the internet?
No, by design. Providers drop fc00::/7 traffic. They are for internal networks, in the same way 192.168.x.x is.
How many subnets do I get from a /48?
65,536 /64 subnets, which is the standard subnet size in IPv6 — far more than almost any private network needs.