How it works
Professional tool to calculate network range, broadcast address, and usable host capacity.
Input query strings and outputs
Use an input name in this page’s URL as ?name=value, and join additional inputs with &. Portable shared links may instead use the compact ?ac= state parameter.
Input query strings
2-
?ip=IP AddressText · Optional · Default: 192.168.1.1
-
?mask=Prefix (/)Number · Optional · Default: 24
Outputs
1-
resultResultText · Primary output
result contains the calculator’s complete rendered result area, including its visible result cards, tables, charts, and messages.
Calculate network ranges, broadcast addresses, and usable hosts
Description
The IP Subnet Calculator is a technical utility for network administrators, IT students, and engineers. Subnetting is the process of dividing a network into smaller, manageable segments. By entering an IP Address and a CIDR mask (prefix length), this tool instantly identifies the boundaries of the network, including the network address, the broadcast address, and the specific range of IP addresses available for devices (hosts).
Inputs
- IP Address: The base address (e.g.,
192.168.1.1). - CIDR (/): The subnet mask bit-count (e.g.,
24for a standard Class C mask).
Outputs
- Network Address: The first address in the subnet (identifies the network).
- Broadcast Address: The last address in the subnet (used for mass communication).
- Host Range: The specific IPs that can be assigned to computers and devices.
- Usable Hosts: The total number of unique devices the subnet can support.
Chart
- N/A: This tool provides direct numeric network results.
“Good to Know”
- Binary Logic: Networking is based on binary math (0s and 1s). The CIDR mask (like /24) tells the computer how many bits are reserved for the “Network” portion versus the “Host” portion.
- The “minus 2” Rule: In any subnet, you lose two addresses: one for the Network ID and one for the Broadcast Address. This is why the usable host count is always $2^{(32-CIDR)} - 2$.
- Private Ranges: Common home networks usually occupy the
192.168.x.x(Class C) or10.x.x.x(Class A) private IP spaces.
Examples
Example 1: Home Network
- Input: 192.168.1.1 / 24
- Output:
- Network: 192.168.1.0
- Broadcast: 192.168.1.255
- Usable Hosts: 254
Example 2: Small Office Subnet
- Input: 10.0.0.50 / 28
- Output:
- Network: 10.0.0.48
- Usable Hosts: 14
Example 3: Point-to-Point Link
- Input: 172.16.0.1 / 30
- Output:
- Network: 172.16.0.0
- Usable Hosts: 2