Enter an address with a CIDR prefix or dotted mask. IPv4 gives network, broadcast, usable range and count, wildcard, the mask in every notation, class and special-use type, and can split the network into 2-16 subnets. IPv6 gives the RFC 5952 canonical and expanded forms, the prefix range and the address type. Errors name the invalid octet or group.
Privacy ledger
Data acquired
None.
Libraries used
Lit 3 — bundled into the tool file itself.
Data stored
None.
Data transmitted
None.
Use it on your own page
Download the tool as a single self-contained HTML file: readable source with the Lit library included, zero network requests — it works opened straight from your disk, and you can customize everything.