This reference lists the private IP address ranges reserved for internal networks (not routable on the public internet) plus the classic IPv4 address classes A–E.
Private & reserved ranges
| Range | CIDR | Use |
|---|---|---|
| 10.0.0.0 – 10.255.255.255 | 10.0.0.0/8 | Private (Class A) |
| 172.16.0.0 – 172.31.255.255 | 172.16.0.0/12 | Private (Class B) |
| 192.168.0.0 – 192.168.255.255 | 192.168.0.0/16 | Private (Class C) |
| 127.0.0.0 – 127.255.255.255 | 127.0.0.0/8 | Loopback (localhost) |
| 169.254.0.0 – 169.254.255.255 | 169.254.0.0/16 | Link-local (APIPA) |
IPv4 address classes
| Class | Range | Use |
|---|---|---|
| A | 1.0.0.0 – 126.255.255.255 | Large networks |
| B | 128.0.0.0 – 191.255.255.255 | Medium networks |
| C | 192.0.0.0 – 223.255.255.255 | Small networks |
| D | 224.0.0.0 – 239.255.255.255 | Multicast |
| E | 240.0.0.0 – 255.255.255.255 | Experimental |