Subnet Calculator
256
254
/24
C
Binary Representations
11000000.10101000.00000001.00000000
11111111.11111111.11111111.00000000
About Subnet Calculator
This free online subnet calculator helps network administrators, developers, and IT professionals quickly determine subnet information for IPv4 addresses. Enter any IP address with either CIDR notation (like /24) or a dotted decimal subnet mask (like 255.255.255.0) to instantly calculate all relevant subnet details.
Subnetting is a fundamental networking concept that divides larger networks into smaller, more manageable segments. This improves network performance by reducing broadcast domains, enhances security through network segmentation, and enables more efficient use of IP address space. Understanding subnetting is essential for network design, troubleshooting, and configuration.
The calculator displays the network address (the first address in the subnet that identifies the network itself), the broadcast address (the last address used for sending data to all hosts), and the range of usable host addresses in between. It also shows the subnet mask in both dotted decimal and CIDR notation, plus the wildcard mask commonly used in access control lists and routing protocols.
All calculations are performed locally in your browser, ensuring your network information remains private. Whether you are planning a new network deployment, configuring firewalls and routers, or studying for networking certifications like CCNA or CompTIA Network+, this tool provides accurate subnet calculations instantly.