A short companion for IPv6 ULA Generator: when it is useful, what it expects, and what to check before using the result.
What it does
Generate a random IPv6 unique local address prefix in fd00::/8, following RFC 4193, for a network that should never be routed on the public internet.
Use the tool
Open IPv6 ULA Generator, add the input the tool asks for, run it, and check the output before using it elsewhere.
Input and output
- Input: text.
- Output: text.
- Category: Network.
Privacy and processing
Processing happens locally in your browser. This tool does not upload the input to ilham.dev.
Questions
What is the difference between fc00::/7 and fd00::/8?
The whole range is fc00::/7. The fd00::/8 half is where the 40-bit global ID is generated locally rather than assigned by a registry, which is the practical choice.
Related guide
For broader background, see Network Debugging Notes.