The IPv6 ULA (Unique Local Address) generator automatically calculates and generates ULA prefixes that comply with RFC 4193 based on the provided MAC address.
What is IPv6 ULA
ULA is a type of local IPv6 address, similar to IPv4 private address ranges. ULA addresses start with fd00::/8, followed by a 40-bit random subnet ID, ensuring global uniqueness. They can be used for internal network communication without requiring public routing.
Core Features
- Generate globally unique ULA prefixes from MAC addresses
- Support ULA-48, ULA-64, and ULA-128 formats
- Uses Web Crypto API to calculate SHA-1 hash
- Supports uppercase/lowercase output
- One-click copy of generated ULA addresses
How to Use
- Enter a MAC address (6 bytes, format: 20:37:06:12:34:56)
- Click generate button to get ULA prefix
- Copy the desired ULA address
Use Cases
- Enterprise internal network IPv6 address planning
- Home network ULA address allocation
- Test environment IPv6 address generation
- Local communication avoiding public address conflicts
Technical Details
The ULA prefix consists of fd + 40-bit subnet ID, where the subnet ID is derived from SHA-1 HMAC calculation of the MAC address, ensuring each MAC address corresponds to a unique ULA prefix.