Subnet Calculator
Calculate subnet with this free online tool
The IP Subnet Calculator simplifies network administration by calculating subnet masks, network addresses, broadcast addresses, and available host IPs. Perfect for network engineers, IT professionals, and students learning networking fundamentals.
Key Features
Calculate subnet masks from CIDR notation
Determine network and broadcast addresses
Count available host addresses instantly
Support for IPv4 subnet calculations
Visual representation of subnet structure
Export calculation results
Subnet Calculator
Enter IP Address
Input the IP address you want to analyze in the format 192.168.1.0
Input CIDR Notation
Enter the CIDR prefix (e.g., /24) or select subnet mask from dropdown
View Results
Instantly see network address, broadcast address, and usable host range
Analyze Details
Review detailed subnet information including first and last usable IPs
Use Cases
Network planning and design for corporate infrastructure
VLSM (Variable Length Subnet Masking) calculations
Troubleshooting connectivity issues in networks
Educational purposes for CompTIA and CCNA certification
Frequently Asked Questions
What is a subnet mask?
A subnet mask is a 32-bit number that divides an IP address into network and host portions, enabling proper routing and network segmentation.
What does CIDR notation mean?
CIDR (Classless Inter-Domain Routing) notation uses a forward slash followed by the number of network bits (e.g., /24), which is more efficient than traditional subnet masks.
How many hosts can I have in a /24 network?
A /24 network has 254 usable host addresses (256 total minus network and broadcast addresses).
Can I calculate IPv6 subnets with this tool?
This calculator focuses on IPv4. For IPv6, you would need a dedicated IPv6 calculator as the subnet structure differs significantly.
Tool Information
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