Class A
Range1.0.0.0–126.255.255.255
First octet0xxxxxxx (0–127)
Default mask/8 (255.0.0.0)
Hosts/network16,777,214
Private10.0.0.0/8
Class B
Range128.0.0.0–191.255.255.255
First octet10xxxxxx (128–191)
Default mask/16 (255.255.0.0)
Hosts/network65,534
Private172.16.0.0/12
Class C
Range192.0.0.0–223.255.255.255
First octet110xxxxx (192–223)
Default mask/24 (255.255.255.0)
Hosts/network254
Private192.168.0.0/16
Class D
Range224.0.0.0–239.255.255.255
First octet1110xxxx (224–239)
UseMulticast groups
No hosts/mask—
Example224.0.0.1 all-hosts
Class E
Range240.0.0.0–255.255.255.255
First octet1111xxxx (240–255)
UseReserved / research
StatusNot used publicly
Exception255.255.255.255 bcast