IPv4 / CIDR Subnet Calculator
Enter an IPv4 address and CIDR prefix (e.g. 192.168.1.0/24) to calculate all subnet parameters immediately.
| CIDR Notation | 192.168.1.0/24 |
|---|---|
| Network Address | 192.168.1.0 |
| Broadcast Address | 192.168.1.255 |
| Subnet Mask | 255.255.255.0 |
| Wildcard Mask | 0.0.0.255 |
| Usable Host Range | 192.168.1.1 - 192.168.1.254 |
| Usable Hosts | 254 |
| Total IP Addresses | 256 |
| IP Type / Class | Private (RFC 1918) · Class C |
| Binary Subnet Mask | 11111111.11111111.11111111.00000000 |
What does the IPv4 Subnet Calculator do and how to use it?
The Herramix IPv4 / CIDR Subnet Calculator is built for network engineers, system administrators, cloud architects, and IT students who need quick, accurate subnetting without doing manual binary math.
Type any IPv4 address into the input box (you can also paste a combined string like 192.168.1.0/24 or 10.0.0.1/16) and select a prefix length from /1 to /32. The table immediately displays the network address, broadcast address, dotted-decimal and binary subnet mask, wildcard mask, usable host IP range, and total usable hosts.
Usage example
Input: Local subnet 192.168.1.0/24
Result: Network address 192.168.1.0 · Broadcast 192.168.1.255 · Subnet mask 255.255.255.0 · Usable range 192.168.1.1 - 192.168.1.254 · 254 usable hosts (256 total addresses).
Frequently Asked Questions
How many usable hosts are in a /24 network like 192.168.1.0/24?
A /24 subnet has 256 total IPv4 addresses and 254 usable host addresses (from 192.168.1.1 to 192.168.1.254), because the first address (.0) is the network identifier and the last address (.255) is reserved for broadcast.
Why do we subtract 2 when calculating usable hosts?
In standard IPv4 networks (/1 to /30), two addresses cannot be assigned to end devices: the network address (all host bits set to 0) and the broadcast address (all host bits set to 1). Therefore, usable hosts equal 2^(32 − CIDR) − 2.
What is a wildcard mask and where is it used?
A wildcard mask is the inverted subnet mask (subtracting each octet from 255). It is widely used in Cisco ACLs (Access Control Lists) and OSPF routing configurations to specify which IP bits must match.
How do /31 and /32 subnets work?
Per RFC 3021, a /31 subnet is designed for point-to-point links and provides 2 usable addresses without a broadcast address. A /32 netmask targets a single specific host (1 address).