About this utility
How to use IPv6 ULA Prefix Generator
Generate a random RFC 4193-style locally assigned /48 prefix with subnet examples.
What to provide
The optional label is mixed with current time and browser cryptographic randomness; it is not transmitted.
- Enter the optional value described above, or leave it empty to generate new values.
- Choose the options that match your intended result.
- Select “Run tool” or press Ctrl/Command + Enter, then copy, download, or move the result back into the first input for another pass.
What the result means
A locally assigned fd00::/8-derived /48 prefix, global ID, sample /64 subnets, and reverse-DNS zone.
Privacy and safety
This utility is loaded as browser code and processes your input only in this tab. OmniCastConverter has no upload endpoint and never stores your content, filenames, tokens, or secrets. Generated markup and code are shown as inert text and are never executed.
Limitations
- This minimizes collision risk but does not coordinate with another site. Do not advertise ULA prefixes on the public Internet.
Try the included example
Select “Load example” at any time to restore this tested sample.
vilnius-lab