Expand compressed 128-bit IPv6 CIDR blocks, calculate prefix ranges, and evaluate /64 subnets.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. Zero egress.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
Type an IPv6 address with prefix (e.g. 2001:db8:85a3::/48).
Review the full uncompressed 8-hextet representation.
Copy start/end network boundaries and /64 subnet counts.
RFC 4291 recommends /64 as the standard subnet prefix for all end-user LANs.
A /48 allocation contains 2^(64-48) = 65,536 distinct /64 networks.
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