About This Tool
Calculate IPv4 subnet details from CIDR notation. Find network address, broadcast address, host range, subnet mask, and the number of available hosts. Essential for network engineers and system administrators.
How to Use
Enter an IPv4 address with CIDR prefix length (e.g., 192.168.1.0/24).
View the calculated subnet details: network address, broadcast address, first and last usable host, subnet mask, and total hosts.
Use the visual subnet map to understand address allocation.
Frequently Asked Questions
What is CIDR notation?
CIDR (Classless Inter-Domain Routing) notation combines an IP address with a prefix length (e.g., 192.168.1.0/24). The prefix length indicates how many bits are used for the network portion.
How many hosts does a /24 subnet have?
A /24 subnet has 256 addresses total (2^8), but 254 usable host addresses. The first address is the network address and the last is the broadcast address.
What is a subnet mask?
A subnet mask separates the network portion from the host portion of an IP address. For /24, the mask is 255.255.255.0, meaning the first 24 bits identify the network.