sysop@hub:~/tools/subnet-calculator$
subnet-calculator
Type an address and prefix (e.g. 192.168.1.0/24) or pick a prefix with the slider. Everything updates live, including a visual map of how the prefix splits the address space.
result
address space map
Each square is one address block. The highlighted region is your subnet inside its /24.
common prefixes
| CIDR | Mask | Usable hosts | Typical use |
|---|
IPv4 only. "Usable hosts" excludes the network and broadcast addresses, except for /31 (point-to-point, RFC 3021) and /32 (single host), which have no broadcast address to exclude.
Related: networking cheat sheet DNS record types troubleshooting wizard