Address (Host or Network) Netmask (i.e. 24) Netmask for sub/supernet (optional)
/ move to:
 



Address:   192.168.128.0         11000000.10101000.10000000 .00000000
Netmask: 255.255.255.0 = 24 11111111.11111111.11111111 .00000000
Wildcard: 0.0.0.255 00000000.00000000.00000000 .11111111
=> Network: 192.168.128.0/24 11000000.10101000.10000000 .00000000 (Class C)
Broadcast: 192.168.128.255 11000000.10101000.10000000 .11111111
HostMin: 192.168.128.1 11000000.10101000.10000000 .00000001
HostMax: 192.168.128.254 11000000.10101000.10000000 .11111110
Hosts/Net: 254 (Private Internet)

Subnets Netmask: 255.255.255.192 = 26 11111111.11111111.11111111.11 000000
Wildcard: 0.0.0.63 00000000.00000000.00000000.00 111111
Network: 192.168.128.0/26 11000000.10101000.10000000.00 000000 (Class C)
Broadcast: 192.168.128.63 11000000.10101000.10000000.00 111111
HostMin: 192.168.128.1 11000000.10101000.10000000.00 000001
HostMax: 192.168.128.62 11000000.10101000.10000000.00 111110
Hosts/Net: 62 (Private Internet)

Network: 192.168.128.64/26 11000000.10101000.10000000.01 000000 (Class C)
Broadcast: 192.168.128.127 11000000.10101000.10000000.01 111111
HostMin: 192.168.128.65 11000000.10101000.10000000.01 000001
HostMax: 192.168.128.126 11000000.10101000.10000000.01 111110
Hosts/Net: 62 (Private Internet)

Network: 192.168.128.128/26 11000000.10101000.10000000.10 000000 (Class C)
Broadcast: 192.168.128.191 11000000.10101000.10000000.10 111111
HostMin: 192.168.128.129 11000000.10101000.10000000.10 000001
HostMax: 192.168.128.190 11000000.10101000.10000000.10 111110
Hosts/Net: 62 (Private Internet)

Network: 192.168.128.192/26 11000000.10101000.10000000.11 000000 (Class C)
Broadcast: 192.168.128.255 11000000.10101000.10000000.11 111111
HostMin: 192.168.128.193 11000000.10101000.10000000.11 000001
HostMax: 192.168.128.254 11000000.10101000.10000000.11 111110
Hosts/Net: 62 (Private Internet)

Subnets: 4
Hosts: 248

Thanks to http://www.netzwerkinfo.de/daemons/ for this ip calculator icon :-)
Version 0.35.2 2005/07/07

Download
07/27/2006 Security information
Screenshot (ipcalc works also at the prompt)
CGI wrapper that produced this page.
Archive
Have a look in the archives for the new version 0.41, with the capability to deaggregate network ranges
How to run this under windows
Debian users can apt-get install ipcalc
2000-2011 Krischan Jodies

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