IP Subnet Calculator

Calculate network address, broadcast, host range, and subnet mask from CIDR notation

IP Address

CIDR Prefix (0–32)

About

CIDR (Classless Inter-Domain Routing) notation specifies an IP address and its associated network prefix. A /24 subnet has 256 addresses (254 usable), /16 has 65,536 (65,534 usable). Network address = IP AND mask; Broadcast = Network OR wildcard.