IP Subnet Calculator
IPv4 CIDR calculator: mask, range, broadcast, hosts.
CIDR notation 192.168.1.0/24 Subnet mask 255.255.255.0 Wildcard mask 0.0.0.255 Network address 192.168.1.0 Broadcast address 192.168.1.255 First usable host 192.168.1.1 Last usable host 192.168.1.254 Total addresses 256 Usable hosts 254 Address class C IP binary 11000000.10101000.00000001.10000010 Mask binary 11111111.11111111.11111111.00000000
About the IP Subnet Calculator
Calculate everything about an IPv4 subnet from an address plus CIDR prefix or dotted mask: network and broadcast addresses, first and last usable hosts, total and usable counts, wildcard mask, address class and binary representations. Private versus public addressing is flagged automatically for the 10.x, 172.16-31.x and 192.168.x ranges.
How to use the IP Subnet Calculator
- Type an IPv4 address in the first field, for example 192.168.1.130.
- Enter a CIDR prefix like /24 or a subnet mask like 255.255.255.0 in the second field.
- Read the summary tiles for network, broadcast and usable host count.
- Open the Subnet details box for the full breakdown including wildcard mask, class and binaries.
IP Subnet Calculator FAQ
Which notations does the mask field accept?
Either a CIDR prefix from 0 to 32 or a dotted subnet mask such as 255.255.255.0 โ the tool converts a valid contiguous mask to its prefix length.
How many usable hosts does a /24 have?
256 total addresses minus the network and broadcast addresses leaves 254 usable hosts; /31 and /32 follow their special point-to-point and host-route rules instead.
How is private or public decided?
The address is checked against the RFC 1918 blocks โ 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16 โ and labeled Private when inside them, Public otherwise.