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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.

Network94.64.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
94.64.0.0
Broadcast address
94.127.255.255
First usable
94.64.0.1
Last usable
94.127.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 5E400000 · Integer 1581252608 to 1585446911
Reverse DNS zones
64.94.in-addr.arpa
65.94.in-addr.arpa
66.94.in-addr.arpa
67.94.in-addr.arpa
68.94.in-addr.arpa
69.94.in-addr.arpa
70.94.in-addr.arpa
71.94.in-addr.arpa
72.94.in-addr.arpa
73.94.in-addr.arpa
74.94.in-addr.arpa
75.94.in-addr.arpa
76.94.in-addr.arpa
77.94.in-addr.arpa
78.94.in-addr.arpa
79.94.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011110.01000000.00000000.0000000094.64.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network01011110.01000000.00000000.0000000094.64.0.0
Broadcast01011110.01111111.11111111.1111111194.127.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

94.64.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
194.64.0.0/2294.64.0.1 to 94.64.3.25494.64.3.2551,022
294.64.4.0/2294.64.4.1 to 94.64.7.25494.64.7.2551,022
394.64.8.0/2294.64.8.1 to 94.64.11.25494.64.11.2551,022
494.64.12.0/2294.64.12.1 to 94.64.15.25494.64.15.2551,022
594.64.16.0/2294.64.16.1 to 94.64.19.25494.64.19.2551,022
694.64.20.0/2294.64.20.1 to 94.64.23.25494.64.23.2551,022
794.64.24.0/2294.64.24.1 to 94.64.27.25494.64.27.2551,022
894.64.28.0/2294.64.28.1 to 94.64.31.25494.64.31.2551,022
994.64.32.0/2294.64.32.1 to 94.64.35.25494.64.35.2551,022
1094.64.36.0/2294.64.36.1 to 94.64.39.25494.64.39.2551,022
1194.64.40.0/2294.64.40.1 to 94.64.43.25494.64.43.2551,022
1294.64.44.0/2294.64.44.1 to 94.64.47.25494.64.47.2551,022
1394.64.48.0/2294.64.48.1 to 94.64.51.25494.64.51.2551,022
1494.64.52.0/2294.64.52.1 to 94.64.55.25494.64.55.2551,022
1594.64.56.0/2294.64.56.1 to 94.64.59.25494.64.59.2551,022
1694.64.60.0/2294.64.60.1 to 94.64.63.25494.64.63.2551,022
1794.64.64.0/2294.64.64.1 to 94.64.67.25494.64.67.2551,022
1894.64.68.0/2294.64.68.1 to 94.64.71.25494.64.71.2551,022
1994.64.72.0/2294.64.72.1 to 94.64.75.25494.64.75.2551,022
2094.64.76.0/2294.64.76.1 to 94.64.79.25494.64.79.2551,022
2194.64.80.0/2294.64.80.1 to 94.64.83.25494.64.83.2551,022
2294.64.84.0/2294.64.84.1 to 94.64.87.25494.64.87.2551,022
2394.64.88.0/2294.64.88.1 to 94.64.91.25494.64.91.2551,022
2494.64.92.0/2294.64.92.1 to 94.64.95.25494.64.95.2551,022
2594.64.96.0/2294.64.96.1 to 94.64.99.25494.64.99.2551,022
2694.64.100.0/2294.64.100.1 to 94.64.103.25494.64.103.2551,022
2794.64.104.0/2294.64.104.1 to 94.64.107.25494.64.107.2551,022
2894.64.108.0/2294.64.108.1 to 94.64.111.25494.64.111.2551,022
2994.64.112.0/2294.64.112.1 to 94.64.115.25494.64.115.2551,022
3094.64.116.0/2294.64.116.1 to 94.64.119.25494.64.119.2551,022
3194.64.120.0/2294.64.120.1 to 94.64.123.25494.64.123.2551,022
3294.64.124.0/2294.64.124.1 to 94.64.127.25494.64.127.2551,022
3394.64.128.0/2294.64.128.1 to 94.64.131.25494.64.131.2551,022
3494.64.132.0/2294.64.132.1 to 94.64.135.25494.64.135.2551,022
3594.64.136.0/2294.64.136.1 to 94.64.139.25494.64.139.2551,022
3694.64.140.0/2294.64.140.1 to 94.64.143.25494.64.143.2551,022
3794.64.144.0/2294.64.144.1 to 94.64.147.25494.64.147.2551,022
3894.64.148.0/2294.64.148.1 to 94.64.151.25494.64.151.2551,022
3994.64.152.0/2294.64.152.1 to 94.64.155.25494.64.155.2551,022
4094.64.156.0/2294.64.156.1 to 94.64.159.25494.64.159.2551,022
4194.64.160.0/2294.64.160.1 to 94.64.163.25494.64.163.2551,022
4294.64.164.0/2294.64.164.1 to 94.64.167.25494.64.167.2551,022
4394.64.168.0/2294.64.168.1 to 94.64.171.25494.64.171.2551,022
4494.64.172.0/2294.64.172.1 to 94.64.175.25494.64.175.2551,022
4594.64.176.0/2294.64.176.1 to 94.64.179.25494.64.179.2551,022
4694.64.180.0/2294.64.180.1 to 94.64.183.25494.64.183.2551,022
4794.64.184.0/2294.64.184.1 to 94.64.187.25494.64.187.2551,022
4894.64.188.0/2294.64.188.1 to 94.64.191.25494.64.191.2551,022
4994.64.192.0/2294.64.192.1 to 94.64.195.25494.64.195.2551,022
5094.64.196.0/2294.64.196.1 to 94.64.199.25494.64.199.2551,022
5194.64.200.0/2294.64.200.1 to 94.64.203.25494.64.203.2551,022
5294.64.204.0/2294.64.204.1 to 94.64.207.25494.64.207.2551,022
5394.64.208.0/2294.64.208.1 to 94.64.211.25494.64.211.2551,022
5494.64.212.0/2294.64.212.1 to 94.64.215.25494.64.215.2551,022
5594.64.216.0/2294.64.216.1 to 94.64.219.25494.64.219.2551,022
5694.64.220.0/2294.64.220.1 to 94.64.223.25494.64.223.2551,022
5794.64.224.0/2294.64.224.1 to 94.64.227.25494.64.227.2551,022
5894.64.228.0/2294.64.228.1 to 94.64.231.25494.64.231.2551,022
5994.64.232.0/2294.64.232.1 to 94.64.235.25494.64.235.2551,022
6094.64.236.0/2294.64.236.1 to 94.64.239.25494.64.239.2551,022
6194.64.240.0/2294.64.240.1 to 94.64.243.25494.64.243.2551,022
6294.64.244.0/2294.64.244.1 to 94.64.247.25494.64.247.2551,022
6394.64.248.0/2294.64.248.1 to 94.64.251.25494.64.251.2551,022
6494.64.252.0/2294.64.252.1 to 94.64.255.25494.64.255.2551,022
6594.65.0.0/2294.65.0.1 to 94.65.3.25494.65.3.2551,022
6694.65.4.0/2294.65.4.1 to 94.65.7.25494.65.7.2551,022
6794.65.8.0/2294.65.8.1 to 94.65.11.25494.65.11.2551,022
6894.65.12.0/2294.65.12.1 to 94.65.15.25494.65.15.2551,022
6994.65.16.0/2294.65.16.1 to 94.65.19.25494.65.19.2551,022
7094.65.20.0/2294.65.20.1 to 94.65.23.25494.65.23.2551,022
7194.65.24.0/2294.65.24.1 to 94.65.27.25494.65.27.2551,022
7294.65.28.0/2294.65.28.1 to 94.65.31.25494.65.31.2551,022
7394.65.32.0/2294.65.32.1 to 94.65.35.25494.65.35.2551,022
7494.65.36.0/2294.65.36.1 to 94.65.39.25494.65.39.2551,022
7594.65.40.0/2294.65.40.1 to 94.65.43.25494.65.43.2551,022
7694.65.44.0/2294.65.44.1 to 94.65.47.25494.65.47.2551,022
7794.65.48.0/2294.65.48.1 to 94.65.51.25494.65.51.2551,022
7894.65.52.0/2294.65.52.1 to 94.65.55.25494.65.55.2551,022
7994.65.56.0/2294.65.56.1 to 94.65.59.25494.65.59.2551,022
8094.65.60.0/2294.65.60.1 to 94.65.63.25494.65.63.2551,022
8194.65.64.0/2294.65.64.1 to 94.65.67.25494.65.67.2551,022
8294.65.68.0/2294.65.68.1 to 94.65.71.25494.65.71.2551,022
8394.65.72.0/2294.65.72.1 to 94.65.75.25494.65.75.2551,022
8494.65.76.0/2294.65.76.1 to 94.65.79.25494.65.79.2551,022
8594.65.80.0/2294.65.80.1 to 94.65.83.25494.65.83.2551,022
8694.65.84.0/2294.65.84.1 to 94.65.87.25494.65.87.2551,022
8794.65.88.0/2294.65.88.1 to 94.65.91.25494.65.91.2551,022
8894.65.92.0/2294.65.92.1 to 94.65.95.25494.65.95.2551,022
8994.65.96.0/2294.65.96.1 to 94.65.99.25494.65.99.2551,022
9094.65.100.0/2294.65.100.1 to 94.65.103.25494.65.103.2551,022
9194.65.104.0/2294.65.104.1 to 94.65.107.25494.65.107.2551,022
9294.65.108.0/2294.65.108.1 to 94.65.111.25494.65.111.2551,022
9394.65.112.0/2294.65.112.1 to 94.65.115.25494.65.115.2551,022
9494.65.116.0/2294.65.116.1 to 94.65.119.25494.65.119.2551,022
9594.65.120.0/2294.65.120.1 to 94.65.123.25494.65.123.2551,022
9694.65.124.0/2294.65.124.1 to 94.65.127.25494.65.127.2551,022
9794.65.128.0/2294.65.128.1 to 94.65.131.25494.65.131.2551,022
9894.65.132.0/2294.65.132.1 to 94.65.135.25494.65.135.2551,022
9994.65.136.0/2294.65.136.1 to 94.65.139.25494.65.139.2551,022
10094.65.140.0/2294.65.140.1 to 94.65.143.25494.65.143.2551,022
10194.65.144.0/2294.65.144.1 to 94.65.147.25494.65.147.2551,022
10294.65.148.0/2294.65.148.1 to 94.65.151.25494.65.151.2551,022
10394.65.152.0/2294.65.152.1 to 94.65.155.25494.65.155.2551,022
10494.65.156.0/2294.65.156.1 to 94.65.159.25494.65.159.2551,022
10594.65.160.0/2294.65.160.1 to 94.65.163.25494.65.163.2551,022
10694.65.164.0/2294.65.164.1 to 94.65.167.25494.65.167.2551,022
10794.65.168.0/2294.65.168.1 to 94.65.171.25494.65.171.2551,022
10894.65.172.0/2294.65.172.1 to 94.65.175.25494.65.175.2551,022
10994.65.176.0/2294.65.176.1 to 94.65.179.25494.65.179.2551,022
11094.65.180.0/2294.65.180.1 to 94.65.183.25494.65.183.2551,022
11194.65.184.0/2294.65.184.1 to 94.65.187.25494.65.187.2551,022
11294.65.188.0/2294.65.188.1 to 94.65.191.25494.65.191.2551,022
11394.65.192.0/2294.65.192.1 to 94.65.195.25494.65.195.2551,022
11494.65.196.0/2294.65.196.1 to 94.65.199.25494.65.199.2551,022
11594.65.200.0/2294.65.200.1 to 94.65.203.25494.65.203.2551,022
11694.65.204.0/2294.65.204.1 to 94.65.207.25494.65.207.2551,022
11794.65.208.0/2294.65.208.1 to 94.65.211.25494.65.211.2551,022
11894.65.212.0/2294.65.212.1 to 94.65.215.25494.65.215.2551,022
11994.65.216.0/2294.65.216.1 to 94.65.219.25494.65.219.2551,022
12094.65.220.0/2294.65.220.1 to 94.65.223.25494.65.223.2551,022
12194.65.224.0/2294.65.224.1 to 94.65.227.25494.65.227.2551,022
12294.65.228.0/2294.65.228.1 to 94.65.231.25494.65.231.2551,022
12394.65.232.0/2294.65.232.1 to 94.65.235.25494.65.235.2551,022
12494.65.236.0/2294.65.236.1 to 94.65.239.25494.65.239.2551,022
12594.65.240.0/2294.65.240.1 to 94.65.243.25494.65.243.2551,022
12694.65.244.0/2294.65.244.1 to 94.65.247.25494.65.247.2551,022
12794.65.248.0/2294.65.248.1 to 94.65.251.25494.65.251.2551,022
12894.65.252.0/2294.65.252.1 to 94.65.255.25494.65.255.2551,022
12994.66.0.0/2294.66.0.1 to 94.66.3.25494.66.3.2551,022
13094.66.4.0/2294.66.4.1 to 94.66.7.25494.66.7.2551,022
13194.66.8.0/2294.66.8.1 to 94.66.11.25494.66.11.2551,022
13294.66.12.0/2294.66.12.1 to 94.66.15.25494.66.15.2551,022
13394.66.16.0/2294.66.16.1 to 94.66.19.25494.66.19.2551,022
13494.66.20.0/2294.66.20.1 to 94.66.23.25494.66.23.2551,022
13594.66.24.0/2294.66.24.1 to 94.66.27.25494.66.27.2551,022
13694.66.28.0/2294.66.28.1 to 94.66.31.25494.66.31.2551,022
13794.66.32.0/2294.66.32.1 to 94.66.35.25494.66.35.2551,022
13894.66.36.0/2294.66.36.1 to 94.66.39.25494.66.39.2551,022
13994.66.40.0/2294.66.40.1 to 94.66.43.25494.66.43.2551,022
14094.66.44.0/2294.66.44.1 to 94.66.47.25494.66.47.2551,022
14194.66.48.0/2294.66.48.1 to 94.66.51.25494.66.51.2551,022
14294.66.52.0/2294.66.52.1 to 94.66.55.25494.66.55.2551,022
14394.66.56.0/2294.66.56.1 to 94.66.59.25494.66.59.2551,022
14494.66.60.0/2294.66.60.1 to 94.66.63.25494.66.63.2551,022
14594.66.64.0/2294.66.64.1 to 94.66.67.25494.66.67.2551,022
14694.66.68.0/2294.66.68.1 to 94.66.71.25494.66.71.2551,022
14794.66.72.0/2294.66.72.1 to 94.66.75.25494.66.75.2551,022
14894.66.76.0/2294.66.76.1 to 94.66.79.25494.66.79.2551,022
14994.66.80.0/2294.66.80.1 to 94.66.83.25494.66.83.2551,022
15094.66.84.0/2294.66.84.1 to 94.66.87.25494.66.87.2551,022
15194.66.88.0/2294.66.88.1 to 94.66.91.25494.66.91.2551,022
15294.66.92.0/2294.66.92.1 to 94.66.95.25494.66.95.2551,022
15394.66.96.0/2294.66.96.1 to 94.66.99.25494.66.99.2551,022
15494.66.100.0/2294.66.100.1 to 94.66.103.25494.66.103.2551,022
15594.66.104.0/2294.66.104.1 to 94.66.107.25494.66.107.2551,022
15694.66.108.0/2294.66.108.1 to 94.66.111.25494.66.111.2551,022
15794.66.112.0/2294.66.112.1 to 94.66.115.25494.66.115.2551,022
15894.66.116.0/2294.66.116.1 to 94.66.119.25494.66.119.2551,022
15994.66.120.0/2294.66.120.1 to 94.66.123.25494.66.123.2551,022
16094.66.124.0/2294.66.124.1 to 94.66.127.25494.66.127.2551,022
16194.66.128.0/2294.66.128.1 to 94.66.131.25494.66.131.2551,022
16294.66.132.0/2294.66.132.1 to 94.66.135.25494.66.135.2551,022
16394.66.136.0/2294.66.136.1 to 94.66.139.25494.66.139.2551,022
16494.66.140.0/2294.66.140.1 to 94.66.143.25494.66.143.2551,022
16594.66.144.0/2294.66.144.1 to 94.66.147.25494.66.147.2551,022
16694.66.148.0/2294.66.148.1 to 94.66.151.25494.66.151.2551,022
16794.66.152.0/2294.66.152.1 to 94.66.155.25494.66.155.2551,022
16894.66.156.0/2294.66.156.1 to 94.66.159.25494.66.159.2551,022
16994.66.160.0/2294.66.160.1 to 94.66.163.25494.66.163.2551,022
17094.66.164.0/2294.66.164.1 to 94.66.167.25494.66.167.2551,022
17194.66.168.0/2294.66.168.1 to 94.66.171.25494.66.171.2551,022
17294.66.172.0/2294.66.172.1 to 94.66.175.25494.66.175.2551,022
17394.66.176.0/2294.66.176.1 to 94.66.179.25494.66.179.2551,022
17494.66.180.0/2294.66.180.1 to 94.66.183.25494.66.183.2551,022
17594.66.184.0/2294.66.184.1 to 94.66.187.25494.66.187.2551,022
17694.66.188.0/2294.66.188.1 to 94.66.191.25494.66.191.2551,022
17794.66.192.0/2294.66.192.1 to 94.66.195.25494.66.195.2551,022
17894.66.196.0/2294.66.196.1 to 94.66.199.25494.66.199.2551,022
17994.66.200.0/2294.66.200.1 to 94.66.203.25494.66.203.2551,022
18094.66.204.0/2294.66.204.1 to 94.66.207.25494.66.207.2551,022
18194.66.208.0/2294.66.208.1 to 94.66.211.25494.66.211.2551,022
18294.66.212.0/2294.66.212.1 to 94.66.215.25494.66.215.2551,022
18394.66.216.0/2294.66.216.1 to 94.66.219.25494.66.219.2551,022
18494.66.220.0/2294.66.220.1 to 94.66.223.25494.66.223.2551,022
18594.66.224.0/2294.66.224.1 to 94.66.227.25494.66.227.2551,022
18694.66.228.0/2294.66.228.1 to 94.66.231.25494.66.231.2551,022
18794.66.232.0/2294.66.232.1 to 94.66.235.25494.66.235.2551,022
18894.66.236.0/2294.66.236.1 to 94.66.239.25494.66.239.2551,022
18994.66.240.0/2294.66.240.1 to 94.66.243.25494.66.243.2551,022
19094.66.244.0/2294.66.244.1 to 94.66.247.25494.66.247.2551,022
19194.66.248.0/2294.66.248.1 to 94.66.251.25494.66.251.2551,022
19294.66.252.0/2294.66.252.1 to 94.66.255.25494.66.255.2551,022
19394.67.0.0/2294.67.0.1 to 94.67.3.25494.67.3.2551,022
19494.67.4.0/2294.67.4.1 to 94.67.7.25494.67.7.2551,022
19594.67.8.0/2294.67.8.1 to 94.67.11.25494.67.11.2551,022
19694.67.12.0/2294.67.12.1 to 94.67.15.25494.67.15.2551,022
19794.67.16.0/2294.67.16.1 to 94.67.19.25494.67.19.2551,022
19894.67.20.0/2294.67.20.1 to 94.67.23.25494.67.23.2551,022
19994.67.24.0/2294.67.24.1 to 94.67.27.25494.67.27.2551,022
20094.67.28.0/2294.67.28.1 to 94.67.31.25494.67.31.2551,022
20194.67.32.0/2294.67.32.1 to 94.67.35.25494.67.35.2551,022
20294.67.36.0/2294.67.36.1 to 94.67.39.25494.67.39.2551,022
20394.67.40.0/2294.67.40.1 to 94.67.43.25494.67.43.2551,022
20494.67.44.0/2294.67.44.1 to 94.67.47.25494.67.47.2551,022
20594.67.48.0/2294.67.48.1 to 94.67.51.25494.67.51.2551,022
20694.67.52.0/2294.67.52.1 to 94.67.55.25494.67.55.2551,022
20794.67.56.0/2294.67.56.1 to 94.67.59.25494.67.59.2551,022
20894.67.60.0/2294.67.60.1 to 94.67.63.25494.67.63.2551,022
20994.67.64.0/2294.67.64.1 to 94.67.67.25494.67.67.2551,022
21094.67.68.0/2294.67.68.1 to 94.67.71.25494.67.71.2551,022
21194.67.72.0/2294.67.72.1 to 94.67.75.25494.67.75.2551,022
21294.67.76.0/2294.67.76.1 to 94.67.79.25494.67.79.2551,022
21394.67.80.0/2294.67.80.1 to 94.67.83.25494.67.83.2551,022
21494.67.84.0/2294.67.84.1 to 94.67.87.25494.67.87.2551,022
21594.67.88.0/2294.67.88.1 to 94.67.91.25494.67.91.2551,022
21694.67.92.0/2294.67.92.1 to 94.67.95.25494.67.95.2551,022
21794.67.96.0/2294.67.96.1 to 94.67.99.25494.67.99.2551,022
21894.67.100.0/2294.67.100.1 to 94.67.103.25494.67.103.2551,022
21994.67.104.0/2294.67.104.1 to 94.67.107.25494.67.107.2551,022
22094.67.108.0/2294.67.108.1 to 94.67.111.25494.67.111.2551,022
22194.67.112.0/2294.67.112.1 to 94.67.115.25494.67.115.2551,022
22294.67.116.0/2294.67.116.1 to 94.67.119.25494.67.119.2551,022
22394.67.120.0/2294.67.120.1 to 94.67.123.25494.67.123.2551,022
22494.67.124.0/2294.67.124.1 to 94.67.127.25494.67.127.2551,022
22594.67.128.0/2294.67.128.1 to 94.67.131.25494.67.131.2551,022
22694.67.132.0/2294.67.132.1 to 94.67.135.25494.67.135.2551,022
22794.67.136.0/2294.67.136.1 to 94.67.139.25494.67.139.2551,022
22894.67.140.0/2294.67.140.1 to 94.67.143.25494.67.143.2551,022
22994.67.144.0/2294.67.144.1 to 94.67.147.25494.67.147.2551,022
23094.67.148.0/2294.67.148.1 to 94.67.151.25494.67.151.2551,022
23194.67.152.0/2294.67.152.1 to 94.67.155.25494.67.155.2551,022
23294.67.156.0/2294.67.156.1 to 94.67.159.25494.67.159.2551,022
23394.67.160.0/2294.67.160.1 to 94.67.163.25494.67.163.2551,022
23494.67.164.0/2294.67.164.1 to 94.67.167.25494.67.167.2551,022
23594.67.168.0/2294.67.168.1 to 94.67.171.25494.67.171.2551,022
23694.67.172.0/2294.67.172.1 to 94.67.175.25494.67.175.2551,022
23794.67.176.0/2294.67.176.1 to 94.67.179.25494.67.179.2551,022
23894.67.180.0/2294.67.180.1 to 94.67.183.25494.67.183.2551,022
23994.67.184.0/2294.67.184.1 to 94.67.187.25494.67.187.2551,022
24094.67.188.0/2294.67.188.1 to 94.67.191.25494.67.191.2551,022
24194.67.192.0/2294.67.192.1 to 94.67.195.25494.67.195.2551,022
24294.67.196.0/2294.67.196.1 to 94.67.199.25494.67.199.2551,022
24394.67.200.0/2294.67.200.1 to 94.67.203.25494.67.203.2551,022
24494.67.204.0/2294.67.204.1 to 94.67.207.25494.67.207.2551,022
24594.67.208.0/2294.67.208.1 to 94.67.211.25494.67.211.2551,022
24694.67.212.0/2294.67.212.1 to 94.67.215.25494.67.215.2551,022
24794.67.216.0/2294.67.216.1 to 94.67.219.25494.67.219.2551,022
24894.67.220.0/2294.67.220.1 to 94.67.223.25494.67.223.2551,022
24994.67.224.0/2294.67.224.1 to 94.67.227.25494.67.227.2551,022
25094.67.228.0/2294.67.228.1 to 94.67.231.25494.67.231.2551,022
25194.67.232.0/2294.67.232.1 to 94.67.235.25494.67.235.2551,022
25294.67.236.0/2294.67.236.1 to 94.67.239.25494.67.239.2551,022
25394.67.240.0/2294.67.240.1 to 94.67.243.25494.67.243.2551,022
25494.67.244.0/2294.67.244.1 to 94.67.247.25494.67.247.2551,022
25594.67.248.0/2294.67.248.1 to 94.67.251.25494.67.251.2551,022
25694.67.252.0/2294.67.252.1 to 94.67.255.25494.67.255.2551,022

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.