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



Address:   192.168.71.0          11000000.10101000.01000111 .00000000
Netmask: 255.255.255.0 = 24 11111111.11111111.11111111 .00000000
Wildcard: 0.0.0.255 00000000.00000000.00000000 .11111111
=> Network: 192.168.71.0/24 11000000.10101000.01000111 .00000000 (Class C)
Broadcast: 192.168.71.255 11000000.10101000.01000111 .11111111
HostMin: 192.168.71.1 11000000.10101000.01000111 .00000001
HostMax: 192.168.71.254 11000000.10101000.01000111 .11111110
Hosts/Net: 254 (Private Internet)

Subnets Netmask: 255.255.255.128 = 25 11111111.11111111.11111111.1 0000000
Wildcard: 0.0.0.127 00000000.00000000.00000000.0 1111111
Network: 192.168.71.0/25 11000000.10101000.01000111.0 0000000 (Class C)
Broadcast: 192.168.71.127 11000000.10101000.01000111.0 1111111
HostMin: 192.168.71.1 11000000.10101000.01000111.0 0000001
HostMax: 192.168.71.126 11000000.10101000.01000111.0 1111110
Hosts/Net: 126 (Private Internet)

Network: 192.168.71.128/25 11000000.10101000.01000111.1 0000000 (Class C)
Broadcast: 192.168.71.255 11000000.10101000.01000111.1 1111111
HostMin: 192.168.71.129 11000000.10101000.01000111.1 0000001
HostMax: 192.168.71.254 11000000.10101000.01000111.1 1111110
Hosts/Net: 126 (Private Internet)

Subnets: 2
Hosts: 252

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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