CIDR Subnet Calculator
Calculate IPv4 subnet masks, network addresses, broadcast IPs, and usable host counts.
Presets:
Usable Hosts
254
Total Addresses
256
IP Class
Class C
Scope
Private (RFC 1918)
Subnet Properties
| Network Address | 192.168.1.0 | |
| Broadcast Address | 192.168.1.255 | |
| Subnet Mask (Netmask) | 255.255.255.0 | |
| Wildcard Mask | 0.0.0.255 | |
| First Usable Host | 192.168.1.1 | |
| Last Usable Host | 192.168.1.254 | |
| IP in Binary | 11000000.10101000.00000001.00000000 | |
| Mask in Binary | 11111111.11111111.11111111.00000000 | |
About CIDR and subnets
This tool reads a CIDR block such as 10.0.0.0/24 and gives the netmask, the network address, the broadcast address, the first and last usable address, and the host count.
The prefix length states how many bits name the network. A smaller number gives a larger block. A /24 holds 256 addresses and 254 usable hosts, because the network address and the broadcast address are reserved.
Use it to plan a VPC, to write a firewall rule, or to check that two subnets do not overlap.