Calculate network addresses, broadcast addresses, host ranges, and subnet masks instantly. Supports both IPv4 CIDR and dotted-decimal notation.
CIDR (Classless Inter-Domain Routing) uses a suffix like /24 to define the number of network bits. A /24 means 256 total addresses with 254 usable hosts.
The subnet mask separates the network portion from the host portion of an IP address. Common masks include 255.255.255.0 (/24) and 255.255.0.0 (/16).
Proper subnetting reduces broadcast domains, improves security through network segmentation, and optimizes IP address allocation across your infrastructure.
| CIDR | Subnet Mask | Total IPs | Usable Hosts | Class |
|---|---|---|---|---|
| /8 | 255.0.0.0 | 16,777,216 | 16,777,214 | A |
| /16 | 255.255.0.0 | 65,536 | 65,534 | B |
| /20 | 255.255.240.0 | 4,096 | 4,094 | - |
| /24 | 255.255.255.0 | 256 | 254 | C |
| /25 | 255.255.255.128 | 128 | 126 | - |
| /26 | 255.255.255.192 | 64 | 62 | - |
| /27 | 255.255.255.224 | 32 | 30 | - |
| /28 | 255.255.255.240 | 16 | 14 | - |
| /29 | 255.255.255.248 | 8 | 6 | - |
| /30 | 255.255.255.252 | 4 | 2 | P2P |
| /31 | 255.255.255.254 | 2 | 2* | P2P |
| /32 | 255.255.255.255 | 1 | 1 | Host |
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