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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network94.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
94.0.0.0
Broadcast address
94.127.255.255
First usable
94.0.0.1
Last usable
94.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 5E000000 · Integer 1577058304 to 1585446911
Reverse DNS zones
0.94.in-addr.arpa
1.94.in-addr.arpa
2.94.in-addr.arpa
3.94.in-addr.arpa
4.94.in-addr.arpa
5.94.in-addr.arpa
6.94.in-addr.arpa
7.94.in-addr.arpa
8.94.in-addr.arpa
9.94.in-addr.arpa
10.94.in-addr.arpa
11.94.in-addr.arpa
12.94.in-addr.arpa
13.94.in-addr.arpa
14.94.in-addr.arpa
15.94.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011110.00000000.00000000.0000000094.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01011110.00000000.00000000.0000000094.0.0.0
Broadcast01011110.01111111.11111111.1111111194.127.255.255
Split into smaller subnets/21
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

94.0.0.0/9 makes 4,096 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
194.0.0.0/2194.0.0.1 to 94.0.7.25494.0.7.2552,046
294.0.8.0/2194.0.8.1 to 94.0.15.25494.0.15.2552,046
394.0.16.0/2194.0.16.1 to 94.0.23.25494.0.23.2552,046
494.0.24.0/2194.0.24.1 to 94.0.31.25494.0.31.2552,046
594.0.32.0/2194.0.32.1 to 94.0.39.25494.0.39.2552,046
694.0.40.0/2194.0.40.1 to 94.0.47.25494.0.47.2552,046
794.0.48.0/2194.0.48.1 to 94.0.55.25494.0.55.2552,046
894.0.56.0/2194.0.56.1 to 94.0.63.25494.0.63.2552,046
994.0.64.0/2194.0.64.1 to 94.0.71.25494.0.71.2552,046
1094.0.72.0/2194.0.72.1 to 94.0.79.25494.0.79.2552,046
1194.0.80.0/2194.0.80.1 to 94.0.87.25494.0.87.2552,046
1294.0.88.0/2194.0.88.1 to 94.0.95.25494.0.95.2552,046
1394.0.96.0/2194.0.96.1 to 94.0.103.25494.0.103.2552,046
1494.0.104.0/2194.0.104.1 to 94.0.111.25494.0.111.2552,046
1594.0.112.0/2194.0.112.1 to 94.0.119.25494.0.119.2552,046
1694.0.120.0/2194.0.120.1 to 94.0.127.25494.0.127.2552,046
1794.0.128.0/2194.0.128.1 to 94.0.135.25494.0.135.2552,046
1894.0.136.0/2194.0.136.1 to 94.0.143.25494.0.143.2552,046
1994.0.144.0/2194.0.144.1 to 94.0.151.25494.0.151.2552,046
2094.0.152.0/2194.0.152.1 to 94.0.159.25494.0.159.2552,046
2194.0.160.0/2194.0.160.1 to 94.0.167.25494.0.167.2552,046
2294.0.168.0/2194.0.168.1 to 94.0.175.25494.0.175.2552,046
2394.0.176.0/2194.0.176.1 to 94.0.183.25494.0.183.2552,046
2494.0.184.0/2194.0.184.1 to 94.0.191.25494.0.191.2552,046
2594.0.192.0/2194.0.192.1 to 94.0.199.25494.0.199.2552,046
2694.0.200.0/2194.0.200.1 to 94.0.207.25494.0.207.2552,046
2794.0.208.0/2194.0.208.1 to 94.0.215.25494.0.215.2552,046
2894.0.216.0/2194.0.216.1 to 94.0.223.25494.0.223.2552,046
2994.0.224.0/2194.0.224.1 to 94.0.231.25494.0.231.2552,046
3094.0.232.0/2194.0.232.1 to 94.0.239.25494.0.239.2552,046
3194.0.240.0/2194.0.240.1 to 94.0.247.25494.0.247.2552,046
3294.0.248.0/2194.0.248.1 to 94.0.255.25494.0.255.2552,046
3394.1.0.0/2194.1.0.1 to 94.1.7.25494.1.7.2552,046
3494.1.8.0/2194.1.8.1 to 94.1.15.25494.1.15.2552,046
3594.1.16.0/2194.1.16.1 to 94.1.23.25494.1.23.2552,046
3694.1.24.0/2194.1.24.1 to 94.1.31.25494.1.31.2552,046
3794.1.32.0/2194.1.32.1 to 94.1.39.25494.1.39.2552,046
3894.1.40.0/2194.1.40.1 to 94.1.47.25494.1.47.2552,046
3994.1.48.0/2194.1.48.1 to 94.1.55.25494.1.55.2552,046
4094.1.56.0/2194.1.56.1 to 94.1.63.25494.1.63.2552,046
4194.1.64.0/2194.1.64.1 to 94.1.71.25494.1.71.2552,046
4294.1.72.0/2194.1.72.1 to 94.1.79.25494.1.79.2552,046
4394.1.80.0/2194.1.80.1 to 94.1.87.25494.1.87.2552,046
4494.1.88.0/2194.1.88.1 to 94.1.95.25494.1.95.2552,046
4594.1.96.0/2194.1.96.1 to 94.1.103.25494.1.103.2552,046
4694.1.104.0/2194.1.104.1 to 94.1.111.25494.1.111.2552,046
4794.1.112.0/2194.1.112.1 to 94.1.119.25494.1.119.2552,046
4894.1.120.0/2194.1.120.1 to 94.1.127.25494.1.127.2552,046
4994.1.128.0/2194.1.128.1 to 94.1.135.25494.1.135.2552,046
5094.1.136.0/2194.1.136.1 to 94.1.143.25494.1.143.2552,046
5194.1.144.0/2194.1.144.1 to 94.1.151.25494.1.151.2552,046
5294.1.152.0/2194.1.152.1 to 94.1.159.25494.1.159.2552,046
5394.1.160.0/2194.1.160.1 to 94.1.167.25494.1.167.2552,046
5494.1.168.0/2194.1.168.1 to 94.1.175.25494.1.175.2552,046
5594.1.176.0/2194.1.176.1 to 94.1.183.25494.1.183.2552,046
5694.1.184.0/2194.1.184.1 to 94.1.191.25494.1.191.2552,046
5794.1.192.0/2194.1.192.1 to 94.1.199.25494.1.199.2552,046
5894.1.200.0/2194.1.200.1 to 94.1.207.25494.1.207.2552,046
5994.1.208.0/2194.1.208.1 to 94.1.215.25494.1.215.2552,046
6094.1.216.0/2194.1.216.1 to 94.1.223.25494.1.223.2552,046
6194.1.224.0/2194.1.224.1 to 94.1.231.25494.1.231.2552,046
6294.1.232.0/2194.1.232.1 to 94.1.239.25494.1.239.2552,046
6394.1.240.0/2194.1.240.1 to 94.1.247.25494.1.247.2552,046
6494.1.248.0/2194.1.248.1 to 94.1.255.25494.1.255.2552,046
6594.2.0.0/2194.2.0.1 to 94.2.7.25494.2.7.2552,046
6694.2.8.0/2194.2.8.1 to 94.2.15.25494.2.15.2552,046
6794.2.16.0/2194.2.16.1 to 94.2.23.25494.2.23.2552,046
6894.2.24.0/2194.2.24.1 to 94.2.31.25494.2.31.2552,046
6994.2.32.0/2194.2.32.1 to 94.2.39.25494.2.39.2552,046
7094.2.40.0/2194.2.40.1 to 94.2.47.25494.2.47.2552,046
7194.2.48.0/2194.2.48.1 to 94.2.55.25494.2.55.2552,046
7294.2.56.0/2194.2.56.1 to 94.2.63.25494.2.63.2552,046
7394.2.64.0/2194.2.64.1 to 94.2.71.25494.2.71.2552,046
7494.2.72.0/2194.2.72.1 to 94.2.79.25494.2.79.2552,046
7594.2.80.0/2194.2.80.1 to 94.2.87.25494.2.87.2552,046
7694.2.88.0/2194.2.88.1 to 94.2.95.25494.2.95.2552,046
7794.2.96.0/2194.2.96.1 to 94.2.103.25494.2.103.2552,046
7894.2.104.0/2194.2.104.1 to 94.2.111.25494.2.111.2552,046
7994.2.112.0/2194.2.112.1 to 94.2.119.25494.2.119.2552,046
8094.2.120.0/2194.2.120.1 to 94.2.127.25494.2.127.2552,046
8194.2.128.0/2194.2.128.1 to 94.2.135.25494.2.135.2552,046
8294.2.136.0/2194.2.136.1 to 94.2.143.25494.2.143.2552,046
8394.2.144.0/2194.2.144.1 to 94.2.151.25494.2.151.2552,046
8494.2.152.0/2194.2.152.1 to 94.2.159.25494.2.159.2552,046
8594.2.160.0/2194.2.160.1 to 94.2.167.25494.2.167.2552,046
8694.2.168.0/2194.2.168.1 to 94.2.175.25494.2.175.2552,046
8794.2.176.0/2194.2.176.1 to 94.2.183.25494.2.183.2552,046
8894.2.184.0/2194.2.184.1 to 94.2.191.25494.2.191.2552,046
8994.2.192.0/2194.2.192.1 to 94.2.199.25494.2.199.2552,046
9094.2.200.0/2194.2.200.1 to 94.2.207.25494.2.207.2552,046
9194.2.208.0/2194.2.208.1 to 94.2.215.25494.2.215.2552,046
9294.2.216.0/2194.2.216.1 to 94.2.223.25494.2.223.2552,046
9394.2.224.0/2194.2.224.1 to 94.2.231.25494.2.231.2552,046
9494.2.232.0/2194.2.232.1 to 94.2.239.25494.2.239.2552,046
9594.2.240.0/2194.2.240.1 to 94.2.247.25494.2.247.2552,046
9694.2.248.0/2194.2.248.1 to 94.2.255.25494.2.255.2552,046
9794.3.0.0/2194.3.0.1 to 94.3.7.25494.3.7.2552,046
9894.3.8.0/2194.3.8.1 to 94.3.15.25494.3.15.2552,046
9994.3.16.0/2194.3.16.1 to 94.3.23.25494.3.23.2552,046
10094.3.24.0/2194.3.24.1 to 94.3.31.25494.3.31.2552,046
10194.3.32.0/2194.3.32.1 to 94.3.39.25494.3.39.2552,046
10294.3.40.0/2194.3.40.1 to 94.3.47.25494.3.47.2552,046
10394.3.48.0/2194.3.48.1 to 94.3.55.25494.3.55.2552,046
10494.3.56.0/2194.3.56.1 to 94.3.63.25494.3.63.2552,046
10594.3.64.0/2194.3.64.1 to 94.3.71.25494.3.71.2552,046
10694.3.72.0/2194.3.72.1 to 94.3.79.25494.3.79.2552,046
10794.3.80.0/2194.3.80.1 to 94.3.87.25494.3.87.2552,046
10894.3.88.0/2194.3.88.1 to 94.3.95.25494.3.95.2552,046
10994.3.96.0/2194.3.96.1 to 94.3.103.25494.3.103.2552,046
11094.3.104.0/2194.3.104.1 to 94.3.111.25494.3.111.2552,046
11194.3.112.0/2194.3.112.1 to 94.3.119.25494.3.119.2552,046
11294.3.120.0/2194.3.120.1 to 94.3.127.25494.3.127.2552,046
11394.3.128.0/2194.3.128.1 to 94.3.135.25494.3.135.2552,046
11494.3.136.0/2194.3.136.1 to 94.3.143.25494.3.143.2552,046
11594.3.144.0/2194.3.144.1 to 94.3.151.25494.3.151.2552,046
11694.3.152.0/2194.3.152.1 to 94.3.159.25494.3.159.2552,046
11794.3.160.0/2194.3.160.1 to 94.3.167.25494.3.167.2552,046
11894.3.168.0/2194.3.168.1 to 94.3.175.25494.3.175.2552,046
11994.3.176.0/2194.3.176.1 to 94.3.183.25494.3.183.2552,046
12094.3.184.0/2194.3.184.1 to 94.3.191.25494.3.191.2552,046
12194.3.192.0/2194.3.192.1 to 94.3.199.25494.3.199.2552,046
12294.3.200.0/2194.3.200.1 to 94.3.207.25494.3.207.2552,046
12394.3.208.0/2194.3.208.1 to 94.3.215.25494.3.215.2552,046
12494.3.216.0/2194.3.216.1 to 94.3.223.25494.3.223.2552,046
12594.3.224.0/2194.3.224.1 to 94.3.231.25494.3.231.2552,046
12694.3.232.0/2194.3.232.1 to 94.3.239.25494.3.239.2552,046
12794.3.240.0/2194.3.240.1 to 94.3.247.25494.3.247.2552,046
12894.3.248.0/2194.3.248.1 to 94.3.255.25494.3.255.2552,046
12994.4.0.0/2194.4.0.1 to 94.4.7.25494.4.7.2552,046
13094.4.8.0/2194.4.8.1 to 94.4.15.25494.4.15.2552,046
13194.4.16.0/2194.4.16.1 to 94.4.23.25494.4.23.2552,046
13294.4.24.0/2194.4.24.1 to 94.4.31.25494.4.31.2552,046
13394.4.32.0/2194.4.32.1 to 94.4.39.25494.4.39.2552,046
13494.4.40.0/2194.4.40.1 to 94.4.47.25494.4.47.2552,046
13594.4.48.0/2194.4.48.1 to 94.4.55.25494.4.55.2552,046
13694.4.56.0/2194.4.56.1 to 94.4.63.25494.4.63.2552,046
13794.4.64.0/2194.4.64.1 to 94.4.71.25494.4.71.2552,046
13894.4.72.0/2194.4.72.1 to 94.4.79.25494.4.79.2552,046
13994.4.80.0/2194.4.80.1 to 94.4.87.25494.4.87.2552,046
14094.4.88.0/2194.4.88.1 to 94.4.95.25494.4.95.2552,046
14194.4.96.0/2194.4.96.1 to 94.4.103.25494.4.103.2552,046
14294.4.104.0/2194.4.104.1 to 94.4.111.25494.4.111.2552,046
14394.4.112.0/2194.4.112.1 to 94.4.119.25494.4.119.2552,046
14494.4.120.0/2194.4.120.1 to 94.4.127.25494.4.127.2552,046
14594.4.128.0/2194.4.128.1 to 94.4.135.25494.4.135.2552,046
14694.4.136.0/2194.4.136.1 to 94.4.143.25494.4.143.2552,046
14794.4.144.0/2194.4.144.1 to 94.4.151.25494.4.151.2552,046
14894.4.152.0/2194.4.152.1 to 94.4.159.25494.4.159.2552,046
14994.4.160.0/2194.4.160.1 to 94.4.167.25494.4.167.2552,046
15094.4.168.0/2194.4.168.1 to 94.4.175.25494.4.175.2552,046
15194.4.176.0/2194.4.176.1 to 94.4.183.25494.4.183.2552,046
15294.4.184.0/2194.4.184.1 to 94.4.191.25494.4.191.2552,046
15394.4.192.0/2194.4.192.1 to 94.4.199.25494.4.199.2552,046
15494.4.200.0/2194.4.200.1 to 94.4.207.25494.4.207.2552,046
15594.4.208.0/2194.4.208.1 to 94.4.215.25494.4.215.2552,046
15694.4.216.0/2194.4.216.1 to 94.4.223.25494.4.223.2552,046
15794.4.224.0/2194.4.224.1 to 94.4.231.25494.4.231.2552,046
15894.4.232.0/2194.4.232.1 to 94.4.239.25494.4.239.2552,046
15994.4.240.0/2194.4.240.1 to 94.4.247.25494.4.247.2552,046
16094.4.248.0/2194.4.248.1 to 94.4.255.25494.4.255.2552,046
16194.5.0.0/2194.5.0.1 to 94.5.7.25494.5.7.2552,046
16294.5.8.0/2194.5.8.1 to 94.5.15.25494.5.15.2552,046
16394.5.16.0/2194.5.16.1 to 94.5.23.25494.5.23.2552,046
16494.5.24.0/2194.5.24.1 to 94.5.31.25494.5.31.2552,046
16594.5.32.0/2194.5.32.1 to 94.5.39.25494.5.39.2552,046
16694.5.40.0/2194.5.40.1 to 94.5.47.25494.5.47.2552,046
16794.5.48.0/2194.5.48.1 to 94.5.55.25494.5.55.2552,046
16894.5.56.0/2194.5.56.1 to 94.5.63.25494.5.63.2552,046
16994.5.64.0/2194.5.64.1 to 94.5.71.25494.5.71.2552,046
17094.5.72.0/2194.5.72.1 to 94.5.79.25494.5.79.2552,046
17194.5.80.0/2194.5.80.1 to 94.5.87.25494.5.87.2552,046
17294.5.88.0/2194.5.88.1 to 94.5.95.25494.5.95.2552,046
17394.5.96.0/2194.5.96.1 to 94.5.103.25494.5.103.2552,046
17494.5.104.0/2194.5.104.1 to 94.5.111.25494.5.111.2552,046
17594.5.112.0/2194.5.112.1 to 94.5.119.25494.5.119.2552,046
17694.5.120.0/2194.5.120.1 to 94.5.127.25494.5.127.2552,046
17794.5.128.0/2194.5.128.1 to 94.5.135.25494.5.135.2552,046
17894.5.136.0/2194.5.136.1 to 94.5.143.25494.5.143.2552,046
17994.5.144.0/2194.5.144.1 to 94.5.151.25494.5.151.2552,046
18094.5.152.0/2194.5.152.1 to 94.5.159.25494.5.159.2552,046
18194.5.160.0/2194.5.160.1 to 94.5.167.25494.5.167.2552,046
18294.5.168.0/2194.5.168.1 to 94.5.175.25494.5.175.2552,046
18394.5.176.0/2194.5.176.1 to 94.5.183.25494.5.183.2552,046
18494.5.184.0/2194.5.184.1 to 94.5.191.25494.5.191.2552,046
18594.5.192.0/2194.5.192.1 to 94.5.199.25494.5.199.2552,046
18694.5.200.0/2194.5.200.1 to 94.5.207.25494.5.207.2552,046
18794.5.208.0/2194.5.208.1 to 94.5.215.25494.5.215.2552,046
18894.5.216.0/2194.5.216.1 to 94.5.223.25494.5.223.2552,046
18994.5.224.0/2194.5.224.1 to 94.5.231.25494.5.231.2552,046
19094.5.232.0/2194.5.232.1 to 94.5.239.25494.5.239.2552,046
19194.5.240.0/2194.5.240.1 to 94.5.247.25494.5.247.2552,046
19294.5.248.0/2194.5.248.1 to 94.5.255.25494.5.255.2552,046
19394.6.0.0/2194.6.0.1 to 94.6.7.25494.6.7.2552,046
19494.6.8.0/2194.6.8.1 to 94.6.15.25494.6.15.2552,046
19594.6.16.0/2194.6.16.1 to 94.6.23.25494.6.23.2552,046
19694.6.24.0/2194.6.24.1 to 94.6.31.25494.6.31.2552,046
19794.6.32.0/2194.6.32.1 to 94.6.39.25494.6.39.2552,046
19894.6.40.0/2194.6.40.1 to 94.6.47.25494.6.47.2552,046
19994.6.48.0/2194.6.48.1 to 94.6.55.25494.6.55.2552,046
20094.6.56.0/2194.6.56.1 to 94.6.63.25494.6.63.2552,046
20194.6.64.0/2194.6.64.1 to 94.6.71.25494.6.71.2552,046
20294.6.72.0/2194.6.72.1 to 94.6.79.25494.6.79.2552,046
20394.6.80.0/2194.6.80.1 to 94.6.87.25494.6.87.2552,046
20494.6.88.0/2194.6.88.1 to 94.6.95.25494.6.95.2552,046
20594.6.96.0/2194.6.96.1 to 94.6.103.25494.6.103.2552,046
20694.6.104.0/2194.6.104.1 to 94.6.111.25494.6.111.2552,046
20794.6.112.0/2194.6.112.1 to 94.6.119.25494.6.119.2552,046
20894.6.120.0/2194.6.120.1 to 94.6.127.25494.6.127.2552,046
20994.6.128.0/2194.6.128.1 to 94.6.135.25494.6.135.2552,046
21094.6.136.0/2194.6.136.1 to 94.6.143.25494.6.143.2552,046
21194.6.144.0/2194.6.144.1 to 94.6.151.25494.6.151.2552,046
21294.6.152.0/2194.6.152.1 to 94.6.159.25494.6.159.2552,046
21394.6.160.0/2194.6.160.1 to 94.6.167.25494.6.167.2552,046
21494.6.168.0/2194.6.168.1 to 94.6.175.25494.6.175.2552,046
21594.6.176.0/2194.6.176.1 to 94.6.183.25494.6.183.2552,046
21694.6.184.0/2194.6.184.1 to 94.6.191.25494.6.191.2552,046
21794.6.192.0/2194.6.192.1 to 94.6.199.25494.6.199.2552,046
21894.6.200.0/2194.6.200.1 to 94.6.207.25494.6.207.2552,046
21994.6.208.0/2194.6.208.1 to 94.6.215.25494.6.215.2552,046
22094.6.216.0/2194.6.216.1 to 94.6.223.25494.6.223.2552,046
22194.6.224.0/2194.6.224.1 to 94.6.231.25494.6.231.2552,046
22294.6.232.0/2194.6.232.1 to 94.6.239.25494.6.239.2552,046
22394.6.240.0/2194.6.240.1 to 94.6.247.25494.6.247.2552,046
22494.6.248.0/2194.6.248.1 to 94.6.255.25494.6.255.2552,046
22594.7.0.0/2194.7.0.1 to 94.7.7.25494.7.7.2552,046
22694.7.8.0/2194.7.8.1 to 94.7.15.25494.7.15.2552,046
22794.7.16.0/2194.7.16.1 to 94.7.23.25494.7.23.2552,046
22894.7.24.0/2194.7.24.1 to 94.7.31.25494.7.31.2552,046
22994.7.32.0/2194.7.32.1 to 94.7.39.25494.7.39.2552,046
23094.7.40.0/2194.7.40.1 to 94.7.47.25494.7.47.2552,046
23194.7.48.0/2194.7.48.1 to 94.7.55.25494.7.55.2552,046
23294.7.56.0/2194.7.56.1 to 94.7.63.25494.7.63.2552,046
23394.7.64.0/2194.7.64.1 to 94.7.71.25494.7.71.2552,046
23494.7.72.0/2194.7.72.1 to 94.7.79.25494.7.79.2552,046
23594.7.80.0/2194.7.80.1 to 94.7.87.25494.7.87.2552,046
23694.7.88.0/2194.7.88.1 to 94.7.95.25494.7.95.2552,046
23794.7.96.0/2194.7.96.1 to 94.7.103.25494.7.103.2552,046
23894.7.104.0/2194.7.104.1 to 94.7.111.25494.7.111.2552,046
23994.7.112.0/2194.7.112.1 to 94.7.119.25494.7.119.2552,046
24094.7.120.0/2194.7.120.1 to 94.7.127.25494.7.127.2552,046
24194.7.128.0/2194.7.128.1 to 94.7.135.25494.7.135.2552,046
24294.7.136.0/2194.7.136.1 to 94.7.143.25494.7.143.2552,046
24394.7.144.0/2194.7.144.1 to 94.7.151.25494.7.151.2552,046
24494.7.152.0/2194.7.152.1 to 94.7.159.25494.7.159.2552,046
24594.7.160.0/2194.7.160.1 to 94.7.167.25494.7.167.2552,046
24694.7.168.0/2194.7.168.1 to 94.7.175.25494.7.175.2552,046
24794.7.176.0/2194.7.176.1 to 94.7.183.25494.7.183.2552,046
24894.7.184.0/2194.7.184.1 to 94.7.191.25494.7.191.2552,046
24994.7.192.0/2194.7.192.1 to 94.7.199.25494.7.199.2552,046
25094.7.200.0/2194.7.200.1 to 94.7.207.25494.7.207.2552,046
25194.7.208.0/2194.7.208.1 to 94.7.215.25494.7.215.2552,046
25294.7.216.0/2194.7.216.1 to 94.7.223.25494.7.223.2552,046
25394.7.224.0/2194.7.224.1 to 94.7.231.25494.7.231.2552,046
25494.7.232.0/2194.7.232.1 to 94.7.239.25494.7.239.2552,046
25594.7.240.0/2194.7.240.1 to 94.7.247.25494.7.247.2552,046
25694.7.248.0/2194.7.248.1 to 94.7.255.25494.7.255.2552,046

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.