Enter an IP address and a subnet mask — dotted decimal (255.255.255.192) or CIDR (/26) — to get the full subnet breakdown.
| CIDR | Subnet mask | Wildcard | Usable hosts | Total addresses |
|---|
A subnet mask splits the 32-bit IPv4 address into a network portion and a host portion. The network address is the first address of the block (all host bits 0); the broadcast address is the last (all host bits 1). Usable host addresses are everything in between — two are always reserved, so a /26 has 64 total addresses but only 62 usable.
Common enterprise allocations: /30 (point-to-point links, 2 hosts), /29 (small transit, 6), /28 (16), /27 (32), /26 (64), /24 (a classic class-C, 254), /23 (512), /22 (1024).
H3C / Huawei / Cisco command map · Network config diff (online) · Config security audit (online) · netops-utils CLI (subnet/diff/audit, zero-dependency Node.js)