CIDR Calculator

Netmask

255.0.0.0

Broadcast Address

127.255.255.255

First Usable IP

127.0.0.1

Last Usable IP

127.255.255.254

Available IPs

16,777,214

Network Type

Class A

Interactive Binary Calculator

IP Address (Binary)

01111111

00000000

00000001

Netmask (Binary)

11111111

00000000

Classless Inter-Domain Routing (or CIDR), is a method for allocating IP addresses for IP routing first introduced in 1993 to replace the previous classful network addressing architecture on the Internet.