Enter an IP address and subnet prefix to instantly calculate the network address, broadcast address, usable host range, and subnet mask — everything you need for network planning and troubleshooting.
Whether you're configuring a router, designing a VLAN, or studying for a networking certification, get accurate subnet details in seconds.
Enter an IPv4 address and select a subnet prefix to calculate full subnet details.
Manual subnetting math is error-prone. This tool gives you accurate results instantly, every time.
Get network address, broadcast address, usable host range, and both masks in one calculation.
See the binary representation of your IP address and subnet mask for deeper understanding.
Instantly see the IP class, whether the address is public or private, and the CIDR notation.
Subnetting divides a larger IP network into smaller, more manageable segments. Each subnet is defined by a network address, a subnet mask (or CIDR prefix), and a range of usable host addresses. The subnet mask determines how many bits are used for the network portion versus the host portion of an address.
This calculator handles the bitwise math automatically — no need to manually convert between binary and decimal, or figure out usable host ranges by hand.
| Common CIDR | Subnet Mask | Usable Hosts |
|---|---|---|
| /24 | 255.255.255.0 | 254 |
| /25 | 255.255.255.128 | 126 |
| /26 | 255.255.255.192 | 62 |
| /30 | 255.255.255.252 | 2 |
Calculate your subnet details in three simple steps.
Type any valid IPv4 address, such as 192.168.1.10 or 10.0.0.5.
Choose the CIDR prefix or subnet mask that matches your network.
Instantly see network address, broadcast, usable range, and binary breakdown.
Common questions about subnetting and this calculator.