Subnet Mask & Range Calculator
Enter an IP with a subnet mask (or CIDR prefix) to get the network address, broadcast address, usable hosts, plus mask-to-CIDR conversion.
Enter IP & Mask
Subnet Result
Subnet Mask ↔ CIDR
Notes
IPv4 only. The mask must have contiguous leading ones (e.g. 255.255.255.0) to map to a valid CIDR prefix.