🌐 IP Subnet Mask & CIDR Calculator
Calculate IPv4 subnet masks, CIDR network prefixes (/24, /16), network IDs, broadcast IPs, and usable host address ranges. 100% free networking tool.
Free No Signup Required Browser-Based
Usable Host IP Range
192.168.1.1 – 192.168.1.254
254 usable assignable hosts (256 total addresses)
Subnet Mask
255.255.255.0Network ID Address
192.168.1.0Broadcast Address
192.168.1.255Wildcard Mask
0.0.0.255How to Use IP Subnet Mask & CIDR Calculator
- Enter the IP address (e.g. 192.168.1.50)
- Select CIDR prefix (/1 to /32)
- Review usable host range, subnet mask, wildcard mask, and network address
📖 Technical Encyclopedia & Standards Reference
Calculate IPv4 subnet masks, CIDR network prefixes (/24, /16), network IDs, broadcast IPs, and usable host address ranges. 100% free networking tool. This tool computes outputs according to official open technical and scientific specifications.
✓ Open Standards AlignmentCompliant with ISO/IEC, W3C, NIST, and standard mathematical formulations.
✓ 100% Client-Side / SecureZero server logging. Computations execute entirely in your local browser sandbox.
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Frequently Asked Questions
What is CIDR notation in networking?
Classless Inter-Domain Routing (CIDR) specifies an IP address and its associated routing prefix (e.g. 192.168.1.0/24 means the first 24 bits are the network prefix).
How do you calculate usable host addresses in a subnet?
Usable Hosts = 2^(32 - CIDR) - 2 (subtracting 2 for the dedicated network ID and broadcast addresses).