IPv4 Subnet Calculator
Parse your IPv4 CIDR blocks and get all the information you need about your subnet.
What is a Subnet?
A subnet is a logically segmented part of an IP network. CIDR notation (e.g. /24) allows flexible definition of network sizes. This calculator shows all relevant addresses at a glance.
Understanding CIDR Notation
CIDR notation specifies how many bits of an IP address identify the network portion. /24 means 256 addresses (254 usable), /16 means 65,536 addresses. The smaller the value, the larger the network.
Wildcard Mask & Broadcast
The wildcard mask is the complement of the subnet mask and is used in Access Control Lists (ACLs). The broadcast address is the highest address in the subnet and is used for network-wide messages.
Frequently Asked Questions
Answers to common questions about the IPv4 Subnet Calculator
An IPv4 subnet is a logically separated portion of a larger IP network. Subnetting allows a large network to be divided into smaller, manageable segments, improving network performance and increasing security.
CIDR notation (Classless Inter-Domain Routing) specifies the number of network bits. /24 means the first 24 bits identify the network address and 8 bits remain for host addresses – giving 256 addresses (254 usable hosts).
The wildcard mask is the complement of the subnet mask and is primarily used in Cisco routers and Access Control Lists (ACLs). A 0 in the wildcard means "must match", a 1 means "any". For /24, the wildcard mask is 0.0.0.255.
The broadcast address is the highest address in a subnet and is used to send packets to all devices in the network. It cannot be assigned to a host. For 192.168.0.0/24, the broadcast address is 192.168.0.255.
Use the "Previous Block" and "Next Block" buttons to navigate through consecutive subnet blocks of the same size. For /24 you would move from 192.168.0.0/24 to 192.168.1.0/24 or back to 192.168.255.0/24.