Subnet Calculator

Calculate IPv4 and IPv6 subnet information.

Network Information

Network Address-
Broadcast Address-
Subnet Mask-
Wildcard Mask-
CIDR Notation-
First Usable Host-
Last Usable Host-
Total Hosts-
Usable Hosts-
IP Class-
IP Type-
Binary Subnet Mask-

Network Information

Compressed-
Expanded-
Network Address-
Network (Expanded)-
Prefix Length-
First Address-
Last Address-
Total Addresses-
Address Type-
/64 Subnets Available-

About CIDR Notation

CIDR (Classless Inter-Domain Routing) is a method for allocating IP addresses and routing. The CIDR notation combines an IP address with its network prefix length.

For example, 192.168.1.0/24 indicates an IPv4 address where the first 24 bits are the network portion, leaving 8 bits for host addresses (256 total, 254 usable).

Common IPv4 Subnet Sizes

CIDR Subnet Mask Total IPs Usable IPs
/24255.255.255.0256254
/25255.255.255.128128126
/26255.255.255.1926462
/27255.255.255.2243230
/28255.255.255.2401614
/29255.255.255.24886
/30255.255.255.25242