By FixTheVuln Team
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Calculate Subnet
Enter an IP address with CIDR prefix (e.g., 192.168.1.0/24) or choose a prefix length below.
Common:
CIDR Quick Reference
| CIDR | Subnet Mask | Wildcard | Total IPs | Usable Hosts |
|---|---|---|---|---|
| /32 | 255.255.255.255 | 0.0.0.0 | 1 | 1 |
| /31 | 255.255.255.254 | 0.0.0.1 | 2 | 2 |
| /30 | 255.255.255.252 | 0.0.0.3 | 4 | 2 |
| /29 | 255.255.255.248 | 0.0.0.7 | 8 | 6 |
| /28 | 255.255.255.240 | 0.0.0.15 | 16 | 14 |
| /27 | 255.255.255.224 | 0.0.0.31 | 32 | 30 |
| /26 | 255.255.255.192 | 0.0.0.63 | 64 | 62 |
| /25 | 255.255.255.128 | 0.0.0.127 | 128 | 126 |
| /24 | 255.255.255.0 | 0.0.0.255 | 256 | 254 |
| /23 | 255.255.254.0 | 0.0.1.255 | 512 | 510 |
| /22 | 255.255.252.0 | 0.0.3.255 | 1,024 | 1,022 |
| /21 | 255.255.248.0 | 0.0.7.255 | 2,048 | 2,046 |
| /20 | 255.255.240.0 | 0.0.15.255 | 4,096 | 4,094 |
| /16 | 255.255.0.0 | 0.0.255.255 | 65,536 | 65,534 |
| /12 | 255.240.0.0 | 0.15.255.255 | 1,048,576 | 1,048,574 |
| /8 | 255.0.0.0 | 0.255.255.255 | 16,777,216 | 16,777,214 |
Private IPv4 Address Ranges (RFC 1918)
| Class | Range | CIDR | Addresses | Common Use |
|---|---|---|---|---|
| A | 10.0.0.0 – 10.255.255.255 | 10.0.0.0/8 | 16,777,216 | Large enterprise networks |
| B | 172.16.0.0 – 172.31.255.255 | 172.16.0.0/12 | 1,048,576 | Medium networks, cloud VPCs |
| C | 192.168.0.0 – 192.168.255.255 | 192.168.0.0/16 | 65,536 | Home and small office networks |
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