IP Address:
Network Address:
Usable Host IP Range:
Broadcast Address:
Total Number of Hosts:
Number of Usable Hosts:
Subnet Mask:
Wildcard Mask:
Binary Subnet Mask:
IP Class:
CIDR Notation:
IP Type:
Short:
Binary ID:
Integer ID:
Hex ID:
in-addr.arpa:
IPv4 Mapped Address:
6to4 Prefix:
A subnet, or subnetwork, is a segmented piece of a larger network. Subnets are designed to improve network performance and security by dividing a large network into smaller, more manageable sections. Each subnet operates as a distinct network, but all subnets within a larger network share a common network address.
A subnet is typically represented in the form of an IP address and a subnet mask. For example, a subnet might look like this:
In this example, the subnet mask 255.255.255.0 indicates that the first three octets (192.168.1) represent the network portion of the address, while the last octet (0) represents the host portion.
| Subnet Mask | CIDR Notation | Number of Hosts |
|---|---|---|
| 255.0.0.0 | /8 | 16,777,214 |
| 255.255.0.0 | /16 | 65,534 |
| 255.255.255.0 | /24 | 254 |
| 255.255.255.128 | /25 | 126 |
| 255.255.255.192 | /26 | 62 |
| 255.255.255.224 | /27 | 30 |
| 255.255.255.240 | /28 | 14 |
| 255.255.255.248 | /29 | 6 |
| 255.255.255.252 | /30 | 2 |
Learning to do this without a calculator? Try the Subnetting Practice tool — unlimited random problems (network/broadcast addresses, masks, host counts, VLSM, IPv6) with step-by-step worked solutions.
From an IP address and a CIDR prefix or subnet mask it derives the network address, broadcast address, usable host range, host count, and wildcard mask, for both IPv4 and IPv6.
It is the prefix length: the first 24 bits identify the network and the remaining 8 identify hosts. A /24 holds 256 addresses, 254 of them usable.
No. All the calculations run locally in your browser; no addresses are transmitted to the server.