CIDR IP Range Calculator

August 26, 2009 7:25 AM

Is there a CIDR IP address calculator that can do what I want? If I enter an arbitrary beginning IP address and an ending IP address, it should then give me a list of CIDR-ified IP ranges.

Lets say I have to authorize an arbitrary range of IP addresses in an .htaccess file. The list looks like XXX.XXX.XXX.97 - XXX.XXX.XXX.255.

I could just set the whole class C range like so, XXX.XXX.XXX.0/24, but that includes IP addresses that should not have access.

The most compact way to display this is as such:
XXX.XXX.XXX.197
XXX.XXX.XXX.198/31
XXX.XXX.XXX.100/30
XXX.XXX.XXX.104/29
XXX.XXX.XXX.112/28
XXX.XXX.XXX.128/25

I can do it with my brain but a tool to help speed this up would be great. Anybody know of one?

posted by chillmost to computers & internet (4 comments total)

This one does that.

Example results for 192.168.1.97 - 192.168.1.255:

Number of subnet for Ip Range
192.168.1.97/255.255.255.255
192.168.1.97/0.0.0.0
CIDR from Netmask
192.168.1.97/32

Number of subnet for Ip Range
192.168.1.98/255.255.255.254
192.168.1.98/0.0.0.1
CIDR from Netmask
192.168.1.98/31

Number of subnet for Ip Range
192.168.1.100/255.255.255.252
192.168.1.100/0.0.0.3
CIDR from Netmask
192.168.1.100/30

Number of subnet for Ip Range
192.168.1.104/255.255.255.248
192.168.1.104/0.0.0.7
CIDR from Netmask
192.168.1.104/29

Number of subnet for Ip Range
192.168.1.112/255.255.255.240
192.168.1.112/0.0.0.15
CIDR from Netmask
192.168.1.112/28

Number of subnet for Ip Range
192.168.1.128/255.255.255.128
192.168.1.128/0.0.0.127
CIDR from Netmask
192.168.1.128/25
posted by jedicus at 8:27 AM on August 26

Or, if you prefer, GIP.
posted by HannoverFist at 8:32 AM on August 26

Forbidden

Ironically, my IP address is not authorized to see the link that jedicus posted. That was always one of the first results that came up when I was googling.

And the download link for GIP isn't working.
posted by chillmost at 10:23 AM on August 26

$ ipcalc 192.168.254.97 - 192.168.254.255
deaggregate 192.168.254.97 - 192.168.254.255
192.168.254.97/32
192.168.254.98/31
192.168.254.100/30
192.168.254.104/29
192.168.254.112/28
192.168.254.128/25

Linix though, don't know if there's a windows version. But there seems to ba a web varsion ipcalc.
posted by zengargoyle at 3:25 PM on August 26