Calculate start IP, end IP, broadcast, subnet mask, and usable hosts from CIDR prefix notations.
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 any IPv4 CIDR block (e.g. 192.168.1.0/24).
View network address, usable host ranges, and binary masks.
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A /24 subnet provides 256 total IP addresses and 254 usable host addresses with a 255.255.255.0 mask.
Yes, RFC 3021 point-to-point /31 subnets are accurately evaluated.
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