IPv4 Network Toolkit
Fast IPv4 subnet calculator and network analyzer
Examples: 192.168.1.25/24 · 10.0.0.1/8 · 172.16.50.20/26 · 192.168.1.25 255.255.255.0
Subnet Splitter
IP Analyzer
Without a prefix you get the decimal / binary / integer conversion only.
Host Calculator
Reference
| CIDR | Subnet Mask | Host Bits | Total Addresses | Usable Hosts |
|---|
/31 (RFC 3021): point-to-point link, both addresses are usable, no network or broadcast address. /32: a single host address, 1 usable. All other prefixes use 2host bits − 2.
Address classes (historical)
| Class | First octet | Default prefix |
|---|---|---|
| A | 1 – 126 (0 and 127 reserved) | /8 |
| B | 128 – 191 | /16 |
| C | 192 – 223 | /24 |
| D | 224 – 239 (multicast) | none |
| E | 240 – 255 (reserved) | none |
Classful addressing is obsolete. Modern routing uses CIDR, where the prefix length alone defines the network.
Private and special ranges
| Range | Purpose |
|---|