Subnet calculator
Classful Network
| Class | Leading bits | Host Address Range | Number of Networks | Notation CIDR | Default Netmask |
|---|---|---|---|---|---|
| Class A | 0 | 0.0.0.0 - 127.255.255.255 | 128 | /8 | 255.0.0.0 |
| Class B | 10 | 128.0.0.0 - 191.255.255.255 | 16384 | /16 | 255.255.0.0 |
| Class C | 110 | 192.0.0.0 - 223.255.255.255 | 2097152 | /24 | 255.255.255.0 |
| Class D (multicast) | 1110 | 224.0.0.0 - 239.255.255.255 | not defined | not defined | |
| Class E (reserved) | 1111 | 240.0.0.0 - 255.255.255.255 | not defined | not defined |
Non-routable networks
The folowing addresses are reseved for private networks:
172.16.0.0 to 172.31.255.255 (172.16 / 12 prefix)
192.168.0.0 to 192.168.255.255 (192.168 / 16 prefix)
Special cases
127.0.0.0 to 127.255.255.255 (LoopBack)
169.254.0.0 to 169.254.255.255 (undeclared hosts)
224.0.0.0 to 239.255.255.255 (Multicast)
This ip address calculator takes IPv4 address and subnet mask or CIDR then calculates and converts to binary ip address, the network address, broadcast address (broadcast), inverse netmask (Cisco wildcard mask), CIDR(Mask Bits), network mask, number of hosts, maximum number of sub-networks, ip range calculator : first and last host address. It is also intended to be a very good educational tool to verify the results and understand the binary values.
Reference : wikipedia: classful network