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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.

Network94.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
94.0.0.0
Broadcast address
95.255.255.255
First usable
94.0.0.1
Last usable
95.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 5E000000 · Integer 1577058304 to 1610612735
Reverse DNS zones
94.in-addr.arpa
95.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011110.00000000.00000000.0000000094.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01011110.00000000.00000000.0000000094.0.0.0
Broadcast01011111.11111111.11111111.1111111195.255.255.255
Split into smaller subnets/16
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

94.0.0.0/7 makes 512 subnets of /16; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
194.0.0.0/1694.0.0.1 to 94.0.255.25494.0.255.25565,534
294.1.0.0/1694.1.0.1 to 94.1.255.25494.1.255.25565,534
394.2.0.0/1694.2.0.1 to 94.2.255.25494.2.255.25565,534
494.3.0.0/1694.3.0.1 to 94.3.255.25494.3.255.25565,534
594.4.0.0/1694.4.0.1 to 94.4.255.25494.4.255.25565,534
694.5.0.0/1694.5.0.1 to 94.5.255.25494.5.255.25565,534
794.6.0.0/1694.6.0.1 to 94.6.255.25494.6.255.25565,534
894.7.0.0/1694.7.0.1 to 94.7.255.25494.7.255.25565,534
994.8.0.0/1694.8.0.1 to 94.8.255.25494.8.255.25565,534
1094.9.0.0/1694.9.0.1 to 94.9.255.25494.9.255.25565,534
1194.10.0.0/1694.10.0.1 to 94.10.255.25494.10.255.25565,534
1294.11.0.0/1694.11.0.1 to 94.11.255.25494.11.255.25565,534
1394.12.0.0/1694.12.0.1 to 94.12.255.25494.12.255.25565,534
1494.13.0.0/1694.13.0.1 to 94.13.255.25494.13.255.25565,534
1594.14.0.0/1694.14.0.1 to 94.14.255.25494.14.255.25565,534
1694.15.0.0/1694.15.0.1 to 94.15.255.25494.15.255.25565,534
1794.16.0.0/1694.16.0.1 to 94.16.255.25494.16.255.25565,534
1894.17.0.0/1694.17.0.1 to 94.17.255.25494.17.255.25565,534
1994.18.0.0/1694.18.0.1 to 94.18.255.25494.18.255.25565,534
2094.19.0.0/1694.19.0.1 to 94.19.255.25494.19.255.25565,534
2194.20.0.0/1694.20.0.1 to 94.20.255.25494.20.255.25565,534
2294.21.0.0/1694.21.0.1 to 94.21.255.25494.21.255.25565,534
2394.22.0.0/1694.22.0.1 to 94.22.255.25494.22.255.25565,534
2494.23.0.0/1694.23.0.1 to 94.23.255.25494.23.255.25565,534
2594.24.0.0/1694.24.0.1 to 94.24.255.25494.24.255.25565,534
2694.25.0.0/1694.25.0.1 to 94.25.255.25494.25.255.25565,534
2794.26.0.0/1694.26.0.1 to 94.26.255.25494.26.255.25565,534
2894.27.0.0/1694.27.0.1 to 94.27.255.25494.27.255.25565,534
2994.28.0.0/1694.28.0.1 to 94.28.255.25494.28.255.25565,534
3094.29.0.0/1694.29.0.1 to 94.29.255.25494.29.255.25565,534
3194.30.0.0/1694.30.0.1 to 94.30.255.25494.30.255.25565,534
3294.31.0.0/1694.31.0.1 to 94.31.255.25494.31.255.25565,534
3394.32.0.0/1694.32.0.1 to 94.32.255.25494.32.255.25565,534
3494.33.0.0/1694.33.0.1 to 94.33.255.25494.33.255.25565,534
3594.34.0.0/1694.34.0.1 to 94.34.255.25494.34.255.25565,534
3694.35.0.0/1694.35.0.1 to 94.35.255.25494.35.255.25565,534
3794.36.0.0/1694.36.0.1 to 94.36.255.25494.36.255.25565,534
3894.37.0.0/1694.37.0.1 to 94.37.255.25494.37.255.25565,534
3994.38.0.0/1694.38.0.1 to 94.38.255.25494.38.255.25565,534
4094.39.0.0/1694.39.0.1 to 94.39.255.25494.39.255.25565,534
4194.40.0.0/1694.40.0.1 to 94.40.255.25494.40.255.25565,534
4294.41.0.0/1694.41.0.1 to 94.41.255.25494.41.255.25565,534
4394.42.0.0/1694.42.0.1 to 94.42.255.25494.42.255.25565,534
4494.43.0.0/1694.43.0.1 to 94.43.255.25494.43.255.25565,534
4594.44.0.0/1694.44.0.1 to 94.44.255.25494.44.255.25565,534
4694.45.0.0/1694.45.0.1 to 94.45.255.25494.45.255.25565,534
4794.46.0.0/1694.46.0.1 to 94.46.255.25494.46.255.25565,534
4894.47.0.0/1694.47.0.1 to 94.47.255.25494.47.255.25565,534
4994.48.0.0/1694.48.0.1 to 94.48.255.25494.48.255.25565,534
5094.49.0.0/1694.49.0.1 to 94.49.255.25494.49.255.25565,534
5194.50.0.0/1694.50.0.1 to 94.50.255.25494.50.255.25565,534
5294.51.0.0/1694.51.0.1 to 94.51.255.25494.51.255.25565,534
5394.52.0.0/1694.52.0.1 to 94.52.255.25494.52.255.25565,534
5494.53.0.0/1694.53.0.1 to 94.53.255.25494.53.255.25565,534
5594.54.0.0/1694.54.0.1 to 94.54.255.25494.54.255.25565,534
5694.55.0.0/1694.55.0.1 to 94.55.255.25494.55.255.25565,534
5794.56.0.0/1694.56.0.1 to 94.56.255.25494.56.255.25565,534
5894.57.0.0/1694.57.0.1 to 94.57.255.25494.57.255.25565,534
5994.58.0.0/1694.58.0.1 to 94.58.255.25494.58.255.25565,534
6094.59.0.0/1694.59.0.1 to 94.59.255.25494.59.255.25565,534
6194.60.0.0/1694.60.0.1 to 94.60.255.25494.60.255.25565,534
6294.61.0.0/1694.61.0.1 to 94.61.255.25494.61.255.25565,534
6394.62.0.0/1694.62.0.1 to 94.62.255.25494.62.255.25565,534
6494.63.0.0/1694.63.0.1 to 94.63.255.25494.63.255.25565,534
6594.64.0.0/1694.64.0.1 to 94.64.255.25494.64.255.25565,534
6694.65.0.0/1694.65.0.1 to 94.65.255.25494.65.255.25565,534
6794.66.0.0/1694.66.0.1 to 94.66.255.25494.66.255.25565,534
6894.67.0.0/1694.67.0.1 to 94.67.255.25494.67.255.25565,534
6994.68.0.0/1694.68.0.1 to 94.68.255.25494.68.255.25565,534
7094.69.0.0/1694.69.0.1 to 94.69.255.25494.69.255.25565,534
7194.70.0.0/1694.70.0.1 to 94.70.255.25494.70.255.25565,534
7294.71.0.0/1694.71.0.1 to 94.71.255.25494.71.255.25565,534
7394.72.0.0/1694.72.0.1 to 94.72.255.25494.72.255.25565,534
7494.73.0.0/1694.73.0.1 to 94.73.255.25494.73.255.25565,534
7594.74.0.0/1694.74.0.1 to 94.74.255.25494.74.255.25565,534
7694.75.0.0/1694.75.0.1 to 94.75.255.25494.75.255.25565,534
7794.76.0.0/1694.76.0.1 to 94.76.255.25494.76.255.25565,534
7894.77.0.0/1694.77.0.1 to 94.77.255.25494.77.255.25565,534
7994.78.0.0/1694.78.0.1 to 94.78.255.25494.78.255.25565,534
8094.79.0.0/1694.79.0.1 to 94.79.255.25494.79.255.25565,534
8194.80.0.0/1694.80.0.1 to 94.80.255.25494.80.255.25565,534
8294.81.0.0/1694.81.0.1 to 94.81.255.25494.81.255.25565,534
8394.82.0.0/1694.82.0.1 to 94.82.255.25494.82.255.25565,534
8494.83.0.0/1694.83.0.1 to 94.83.255.25494.83.255.25565,534
8594.84.0.0/1694.84.0.1 to 94.84.255.25494.84.255.25565,534
8694.85.0.0/1694.85.0.1 to 94.85.255.25494.85.255.25565,534
8794.86.0.0/1694.86.0.1 to 94.86.255.25494.86.255.25565,534
8894.87.0.0/1694.87.0.1 to 94.87.255.25494.87.255.25565,534
8994.88.0.0/1694.88.0.1 to 94.88.255.25494.88.255.25565,534
9094.89.0.0/1694.89.0.1 to 94.89.255.25494.89.255.25565,534
9194.90.0.0/1694.90.0.1 to 94.90.255.25494.90.255.25565,534
9294.91.0.0/1694.91.0.1 to 94.91.255.25494.91.255.25565,534
9394.92.0.0/1694.92.0.1 to 94.92.255.25494.92.255.25565,534
9494.93.0.0/1694.93.0.1 to 94.93.255.25494.93.255.25565,534
9594.94.0.0/1694.94.0.1 to 94.94.255.25494.94.255.25565,534
9694.95.0.0/1694.95.0.1 to 94.95.255.25494.95.255.25565,534
9794.96.0.0/1694.96.0.1 to 94.96.255.25494.96.255.25565,534
9894.97.0.0/1694.97.0.1 to 94.97.255.25494.97.255.25565,534
9994.98.0.0/1694.98.0.1 to 94.98.255.25494.98.255.25565,534
10094.99.0.0/1694.99.0.1 to 94.99.255.25494.99.255.25565,534
10194.100.0.0/1694.100.0.1 to 94.100.255.25494.100.255.25565,534
10294.101.0.0/1694.101.0.1 to 94.101.255.25494.101.255.25565,534
10394.102.0.0/1694.102.0.1 to 94.102.255.25494.102.255.25565,534
10494.103.0.0/1694.103.0.1 to 94.103.255.25494.103.255.25565,534
10594.104.0.0/1694.104.0.1 to 94.104.255.25494.104.255.25565,534
10694.105.0.0/1694.105.0.1 to 94.105.255.25494.105.255.25565,534
10794.106.0.0/1694.106.0.1 to 94.106.255.25494.106.255.25565,534
10894.107.0.0/1694.107.0.1 to 94.107.255.25494.107.255.25565,534
10994.108.0.0/1694.108.0.1 to 94.108.255.25494.108.255.25565,534
11094.109.0.0/1694.109.0.1 to 94.109.255.25494.109.255.25565,534
11194.110.0.0/1694.110.0.1 to 94.110.255.25494.110.255.25565,534
11294.111.0.0/1694.111.0.1 to 94.111.255.25494.111.255.25565,534
11394.112.0.0/1694.112.0.1 to 94.112.255.25494.112.255.25565,534
11494.113.0.0/1694.113.0.1 to 94.113.255.25494.113.255.25565,534
11594.114.0.0/1694.114.0.1 to 94.114.255.25494.114.255.25565,534
11694.115.0.0/1694.115.0.1 to 94.115.255.25494.115.255.25565,534
11794.116.0.0/1694.116.0.1 to 94.116.255.25494.116.255.25565,534
11894.117.0.0/1694.117.0.1 to 94.117.255.25494.117.255.25565,534
11994.118.0.0/1694.118.0.1 to 94.118.255.25494.118.255.25565,534
12094.119.0.0/1694.119.0.1 to 94.119.255.25494.119.255.25565,534
12194.120.0.0/1694.120.0.1 to 94.120.255.25494.120.255.25565,534
12294.121.0.0/1694.121.0.1 to 94.121.255.25494.121.255.25565,534
12394.122.0.0/1694.122.0.1 to 94.122.255.25494.122.255.25565,534
12494.123.0.0/1694.123.0.1 to 94.123.255.25494.123.255.25565,534
12594.124.0.0/1694.124.0.1 to 94.124.255.25494.124.255.25565,534
12694.125.0.0/1694.125.0.1 to 94.125.255.25494.125.255.25565,534
12794.126.0.0/1694.126.0.1 to 94.126.255.25494.126.255.25565,534
12894.127.0.0/1694.127.0.1 to 94.127.255.25494.127.255.25565,534
12994.128.0.0/1694.128.0.1 to 94.128.255.25494.128.255.25565,534
13094.129.0.0/1694.129.0.1 to 94.129.255.25494.129.255.25565,534
13194.130.0.0/1694.130.0.1 to 94.130.255.25494.130.255.25565,534
13294.131.0.0/1694.131.0.1 to 94.131.255.25494.131.255.25565,534
13394.132.0.0/1694.132.0.1 to 94.132.255.25494.132.255.25565,534
13494.133.0.0/1694.133.0.1 to 94.133.255.25494.133.255.25565,534
13594.134.0.0/1694.134.0.1 to 94.134.255.25494.134.255.25565,534
13694.135.0.0/1694.135.0.1 to 94.135.255.25494.135.255.25565,534
13794.136.0.0/1694.136.0.1 to 94.136.255.25494.136.255.25565,534
13894.137.0.0/1694.137.0.1 to 94.137.255.25494.137.255.25565,534
13994.138.0.0/1694.138.0.1 to 94.138.255.25494.138.255.25565,534
14094.139.0.0/1694.139.0.1 to 94.139.255.25494.139.255.25565,534
14194.140.0.0/1694.140.0.1 to 94.140.255.25494.140.255.25565,534
14294.141.0.0/1694.141.0.1 to 94.141.255.25494.141.255.25565,534
14394.142.0.0/1694.142.0.1 to 94.142.255.25494.142.255.25565,534
14494.143.0.0/1694.143.0.1 to 94.143.255.25494.143.255.25565,534
14594.144.0.0/1694.144.0.1 to 94.144.255.25494.144.255.25565,534
14694.145.0.0/1694.145.0.1 to 94.145.255.25494.145.255.25565,534
14794.146.0.0/1694.146.0.1 to 94.146.255.25494.146.255.25565,534
14894.147.0.0/1694.147.0.1 to 94.147.255.25494.147.255.25565,534
14994.148.0.0/1694.148.0.1 to 94.148.255.25494.148.255.25565,534
15094.149.0.0/1694.149.0.1 to 94.149.255.25494.149.255.25565,534
15194.150.0.0/1694.150.0.1 to 94.150.255.25494.150.255.25565,534
15294.151.0.0/1694.151.0.1 to 94.151.255.25494.151.255.25565,534
15394.152.0.0/1694.152.0.1 to 94.152.255.25494.152.255.25565,534
15494.153.0.0/1694.153.0.1 to 94.153.255.25494.153.255.25565,534
15594.154.0.0/1694.154.0.1 to 94.154.255.25494.154.255.25565,534
15694.155.0.0/1694.155.0.1 to 94.155.255.25494.155.255.25565,534
15794.156.0.0/1694.156.0.1 to 94.156.255.25494.156.255.25565,534
15894.157.0.0/1694.157.0.1 to 94.157.255.25494.157.255.25565,534
15994.158.0.0/1694.158.0.1 to 94.158.255.25494.158.255.25565,534
16094.159.0.0/1694.159.0.1 to 94.159.255.25494.159.255.25565,534
16194.160.0.0/1694.160.0.1 to 94.160.255.25494.160.255.25565,534
16294.161.0.0/1694.161.0.1 to 94.161.255.25494.161.255.25565,534
16394.162.0.0/1694.162.0.1 to 94.162.255.25494.162.255.25565,534
16494.163.0.0/1694.163.0.1 to 94.163.255.25494.163.255.25565,534
16594.164.0.0/1694.164.0.1 to 94.164.255.25494.164.255.25565,534
16694.165.0.0/1694.165.0.1 to 94.165.255.25494.165.255.25565,534
16794.166.0.0/1694.166.0.1 to 94.166.255.25494.166.255.25565,534
16894.167.0.0/1694.167.0.1 to 94.167.255.25494.167.255.25565,534
16994.168.0.0/1694.168.0.1 to 94.168.255.25494.168.255.25565,534
17094.169.0.0/1694.169.0.1 to 94.169.255.25494.169.255.25565,534
17194.170.0.0/1694.170.0.1 to 94.170.255.25494.170.255.25565,534
17294.171.0.0/1694.171.0.1 to 94.171.255.25494.171.255.25565,534
17394.172.0.0/1694.172.0.1 to 94.172.255.25494.172.255.25565,534
17494.173.0.0/1694.173.0.1 to 94.173.255.25494.173.255.25565,534
17594.174.0.0/1694.174.0.1 to 94.174.255.25494.174.255.25565,534
17694.175.0.0/1694.175.0.1 to 94.175.255.25494.175.255.25565,534
17794.176.0.0/1694.176.0.1 to 94.176.255.25494.176.255.25565,534
17894.177.0.0/1694.177.0.1 to 94.177.255.25494.177.255.25565,534
17994.178.0.0/1694.178.0.1 to 94.178.255.25494.178.255.25565,534
18094.179.0.0/1694.179.0.1 to 94.179.255.25494.179.255.25565,534
18194.180.0.0/1694.180.0.1 to 94.180.255.25494.180.255.25565,534
18294.181.0.0/1694.181.0.1 to 94.181.255.25494.181.255.25565,534
18394.182.0.0/1694.182.0.1 to 94.182.255.25494.182.255.25565,534
18494.183.0.0/1694.183.0.1 to 94.183.255.25494.183.255.25565,534
18594.184.0.0/1694.184.0.1 to 94.184.255.25494.184.255.25565,534
18694.185.0.0/1694.185.0.1 to 94.185.255.25494.185.255.25565,534
18794.186.0.0/1694.186.0.1 to 94.186.255.25494.186.255.25565,534
18894.187.0.0/1694.187.0.1 to 94.187.255.25494.187.255.25565,534
18994.188.0.0/1694.188.0.1 to 94.188.255.25494.188.255.25565,534
19094.189.0.0/1694.189.0.1 to 94.189.255.25494.189.255.25565,534
19194.190.0.0/1694.190.0.1 to 94.190.255.25494.190.255.25565,534
19294.191.0.0/1694.191.0.1 to 94.191.255.25494.191.255.25565,534
19394.192.0.0/1694.192.0.1 to 94.192.255.25494.192.255.25565,534
19494.193.0.0/1694.193.0.1 to 94.193.255.25494.193.255.25565,534
19594.194.0.0/1694.194.0.1 to 94.194.255.25494.194.255.25565,534
19694.195.0.0/1694.195.0.1 to 94.195.255.25494.195.255.25565,534
19794.196.0.0/1694.196.0.1 to 94.196.255.25494.196.255.25565,534
19894.197.0.0/1694.197.0.1 to 94.197.255.25494.197.255.25565,534
19994.198.0.0/1694.198.0.1 to 94.198.255.25494.198.255.25565,534
20094.199.0.0/1694.199.0.1 to 94.199.255.25494.199.255.25565,534
20194.200.0.0/1694.200.0.1 to 94.200.255.25494.200.255.25565,534
20294.201.0.0/1694.201.0.1 to 94.201.255.25494.201.255.25565,534
20394.202.0.0/1694.202.0.1 to 94.202.255.25494.202.255.25565,534
20494.203.0.0/1694.203.0.1 to 94.203.255.25494.203.255.25565,534
20594.204.0.0/1694.204.0.1 to 94.204.255.25494.204.255.25565,534
20694.205.0.0/1694.205.0.1 to 94.205.255.25494.205.255.25565,534
20794.206.0.0/1694.206.0.1 to 94.206.255.25494.206.255.25565,534
20894.207.0.0/1694.207.0.1 to 94.207.255.25494.207.255.25565,534
20994.208.0.0/1694.208.0.1 to 94.208.255.25494.208.255.25565,534
21094.209.0.0/1694.209.0.1 to 94.209.255.25494.209.255.25565,534
21194.210.0.0/1694.210.0.1 to 94.210.255.25494.210.255.25565,534
21294.211.0.0/1694.211.0.1 to 94.211.255.25494.211.255.25565,534
21394.212.0.0/1694.212.0.1 to 94.212.255.25494.212.255.25565,534
21494.213.0.0/1694.213.0.1 to 94.213.255.25494.213.255.25565,534
21594.214.0.0/1694.214.0.1 to 94.214.255.25494.214.255.25565,534
21694.215.0.0/1694.215.0.1 to 94.215.255.25494.215.255.25565,534
21794.216.0.0/1694.216.0.1 to 94.216.255.25494.216.255.25565,534
21894.217.0.0/1694.217.0.1 to 94.217.255.25494.217.255.25565,534
21994.218.0.0/1694.218.0.1 to 94.218.255.25494.218.255.25565,534
22094.219.0.0/1694.219.0.1 to 94.219.255.25494.219.255.25565,534
22194.220.0.0/1694.220.0.1 to 94.220.255.25494.220.255.25565,534
22294.221.0.0/1694.221.0.1 to 94.221.255.25494.221.255.25565,534
22394.222.0.0/1694.222.0.1 to 94.222.255.25494.222.255.25565,534
22494.223.0.0/1694.223.0.1 to 94.223.255.25494.223.255.25565,534
22594.224.0.0/1694.224.0.1 to 94.224.255.25494.224.255.25565,534
22694.225.0.0/1694.225.0.1 to 94.225.255.25494.225.255.25565,534
22794.226.0.0/1694.226.0.1 to 94.226.255.25494.226.255.25565,534
22894.227.0.0/1694.227.0.1 to 94.227.255.25494.227.255.25565,534
22994.228.0.0/1694.228.0.1 to 94.228.255.25494.228.255.25565,534
23094.229.0.0/1694.229.0.1 to 94.229.255.25494.229.255.25565,534
23194.230.0.0/1694.230.0.1 to 94.230.255.25494.230.255.25565,534
23294.231.0.0/1694.231.0.1 to 94.231.255.25494.231.255.25565,534
23394.232.0.0/1694.232.0.1 to 94.232.255.25494.232.255.25565,534
23494.233.0.0/1694.233.0.1 to 94.233.255.25494.233.255.25565,534
23594.234.0.0/1694.234.0.1 to 94.234.255.25494.234.255.25565,534
23694.235.0.0/1694.235.0.1 to 94.235.255.25494.235.255.25565,534
23794.236.0.0/1694.236.0.1 to 94.236.255.25494.236.255.25565,534
23894.237.0.0/1694.237.0.1 to 94.237.255.25494.237.255.25565,534
23994.238.0.0/1694.238.0.1 to 94.238.255.25494.238.255.25565,534
24094.239.0.0/1694.239.0.1 to 94.239.255.25494.239.255.25565,534
24194.240.0.0/1694.240.0.1 to 94.240.255.25494.240.255.25565,534
24294.241.0.0/1694.241.0.1 to 94.241.255.25494.241.255.25565,534
24394.242.0.0/1694.242.0.1 to 94.242.255.25494.242.255.25565,534
24494.243.0.0/1694.243.0.1 to 94.243.255.25494.243.255.25565,534
24594.244.0.0/1694.244.0.1 to 94.244.255.25494.244.255.25565,534
24694.245.0.0/1694.245.0.1 to 94.245.255.25494.245.255.25565,534
24794.246.0.0/1694.246.0.1 to 94.246.255.25494.246.255.25565,534
24894.247.0.0/1694.247.0.1 to 94.247.255.25494.247.255.25565,534
24994.248.0.0/1694.248.0.1 to 94.248.255.25494.248.255.25565,534
25094.249.0.0/1694.249.0.1 to 94.249.255.25494.249.255.25565,534
25194.250.0.0/1694.250.0.1 to 94.250.255.25494.250.255.25565,534
25294.251.0.0/1694.251.0.1 to 94.251.255.25494.251.255.25565,534
25394.252.0.0/1694.252.0.1 to 94.252.255.25494.252.255.25565,534
25494.253.0.0/1694.253.0.1 to 94.253.255.25494.253.255.25565,534
25594.254.0.0/1694.254.0.1 to 94.254.255.25494.254.255.25565,534
25694.255.0.0/1694.255.0.1 to 94.255.255.25494.255.255.25565,534

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.