IP Subnet Calculator
Calculate subnets and network addresses
Network Configuration
Quick Reference
Private IP Ranges:
- • 10.0.0.0/8
- • 172.16.0.0/12
- • 192.168.0.0/16
Common Masks:
- • /24 = 254 hosts
- • /25 = 126 hosts
- • /26 = 62 hosts
- • /27 = 30 hosts
Network Summary
Network:192.168.1.0/24
Broadcast:192.168.1.255
IP Class:Class C (Private)
Total Hosts
256
addresses
Usable Hosts
254
minus network/broadcast
Host Range
First Host:192.168.1.1
Last Host:192.168.1.254
Wildcard:0.0.0.255
Binary Format
Network:
11000000.10101000.00000001.00000000
Netmask:
11111111.11111111.11111111.00000000
Hex:C0:A8:01:00
How it works
A subnet calculator breaks an IP network into the parts that matter: the network address, the subnet mask, and the range of usable host addresses. The CIDR prefix (like /24) says how many bits identify the network; the rest identify hosts.
Hosts per subnet
Usable hosts = 2^(32 − prefix) − 2
- prefix
- CIDR network bits (e.g. 24 in /24)
- − 2
- reserve the network and broadcast addresses
Worked example
- Network 192.168.1.0/24
- Host bits = 32 − 24 = 8
- Usable = 2⁸ − 2
254 usable host addresses (mask 255.255.255.0).
Good to know
- The first address is the network ID and the last is broadcast — neither is assignable, hence the −2.
- A smaller prefix (/16) means a bigger network; a larger one (/30) means a tiny subnet.
- Subnetting splits one block into several smaller, isolated networks.