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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.

Network46.100.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
46.100.0.0
Broadcast address
46.103.255.255
First usable
46.100.0.1
Last usable
46.103.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 2E640000 · Integer 778305536 to 778567679
Reverse DNS zones
100.46.in-addr.arpa
101.46.in-addr.arpa
102.46.in-addr.arpa
103.46.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101110.01100100.00000000.0000000046.100.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00101110.01100100.00000000.0000000046.100.0.0
Broadcast00101110.01100111.11111111.1111111146.103.255.255
Split into smaller subnets/23
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

46.100.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
146.100.0.0/2346.100.0.1 to 46.100.1.25446.100.1.255510
246.100.2.0/2346.100.2.1 to 46.100.3.25446.100.3.255510
346.100.4.0/2346.100.4.1 to 46.100.5.25446.100.5.255510
446.100.6.0/2346.100.6.1 to 46.100.7.25446.100.7.255510
546.100.8.0/2346.100.8.1 to 46.100.9.25446.100.9.255510
646.100.10.0/2346.100.10.1 to 46.100.11.25446.100.11.255510
746.100.12.0/2346.100.12.1 to 46.100.13.25446.100.13.255510
846.100.14.0/2346.100.14.1 to 46.100.15.25446.100.15.255510
946.100.16.0/2346.100.16.1 to 46.100.17.25446.100.17.255510
1046.100.18.0/2346.100.18.1 to 46.100.19.25446.100.19.255510
1146.100.20.0/2346.100.20.1 to 46.100.21.25446.100.21.255510
1246.100.22.0/2346.100.22.1 to 46.100.23.25446.100.23.255510
1346.100.24.0/2346.100.24.1 to 46.100.25.25446.100.25.255510
1446.100.26.0/2346.100.26.1 to 46.100.27.25446.100.27.255510
1546.100.28.0/2346.100.28.1 to 46.100.29.25446.100.29.255510
1646.100.30.0/2346.100.30.1 to 46.100.31.25446.100.31.255510
1746.100.32.0/2346.100.32.1 to 46.100.33.25446.100.33.255510
1846.100.34.0/2346.100.34.1 to 46.100.35.25446.100.35.255510
1946.100.36.0/2346.100.36.1 to 46.100.37.25446.100.37.255510
2046.100.38.0/2346.100.38.1 to 46.100.39.25446.100.39.255510
2146.100.40.0/2346.100.40.1 to 46.100.41.25446.100.41.255510
2246.100.42.0/2346.100.42.1 to 46.100.43.25446.100.43.255510
2346.100.44.0/2346.100.44.1 to 46.100.45.25446.100.45.255510
2446.100.46.0/2346.100.46.1 to 46.100.47.25446.100.47.255510
2546.100.48.0/2346.100.48.1 to 46.100.49.25446.100.49.255510
2646.100.50.0/2346.100.50.1 to 46.100.51.25446.100.51.255510
2746.100.52.0/2346.100.52.1 to 46.100.53.25446.100.53.255510
2846.100.54.0/2346.100.54.1 to 46.100.55.25446.100.55.255510
2946.100.56.0/2346.100.56.1 to 46.100.57.25446.100.57.255510
3046.100.58.0/2346.100.58.1 to 46.100.59.25446.100.59.255510
3146.100.60.0/2346.100.60.1 to 46.100.61.25446.100.61.255510
3246.100.62.0/2346.100.62.1 to 46.100.63.25446.100.63.255510
3346.100.64.0/2346.100.64.1 to 46.100.65.25446.100.65.255510
3446.100.66.0/2346.100.66.1 to 46.100.67.25446.100.67.255510
3546.100.68.0/2346.100.68.1 to 46.100.69.25446.100.69.255510
3646.100.70.0/2346.100.70.1 to 46.100.71.25446.100.71.255510
3746.100.72.0/2346.100.72.1 to 46.100.73.25446.100.73.255510
3846.100.74.0/2346.100.74.1 to 46.100.75.25446.100.75.255510
3946.100.76.0/2346.100.76.1 to 46.100.77.25446.100.77.255510
4046.100.78.0/2346.100.78.1 to 46.100.79.25446.100.79.255510
4146.100.80.0/2346.100.80.1 to 46.100.81.25446.100.81.255510
4246.100.82.0/2346.100.82.1 to 46.100.83.25446.100.83.255510
4346.100.84.0/2346.100.84.1 to 46.100.85.25446.100.85.255510
4446.100.86.0/2346.100.86.1 to 46.100.87.25446.100.87.255510
4546.100.88.0/2346.100.88.1 to 46.100.89.25446.100.89.255510
4646.100.90.0/2346.100.90.1 to 46.100.91.25446.100.91.255510
4746.100.92.0/2346.100.92.1 to 46.100.93.25446.100.93.255510
4846.100.94.0/2346.100.94.1 to 46.100.95.25446.100.95.255510
4946.100.96.0/2346.100.96.1 to 46.100.97.25446.100.97.255510
5046.100.98.0/2346.100.98.1 to 46.100.99.25446.100.99.255510
5146.100.100.0/2346.100.100.1 to 46.100.101.25446.100.101.255510
5246.100.102.0/2346.100.102.1 to 46.100.103.25446.100.103.255510
5346.100.104.0/2346.100.104.1 to 46.100.105.25446.100.105.255510
5446.100.106.0/2346.100.106.1 to 46.100.107.25446.100.107.255510
5546.100.108.0/2346.100.108.1 to 46.100.109.25446.100.109.255510
5646.100.110.0/2346.100.110.1 to 46.100.111.25446.100.111.255510
5746.100.112.0/2346.100.112.1 to 46.100.113.25446.100.113.255510
5846.100.114.0/2346.100.114.1 to 46.100.115.25446.100.115.255510
5946.100.116.0/2346.100.116.1 to 46.100.117.25446.100.117.255510
6046.100.118.0/2346.100.118.1 to 46.100.119.25446.100.119.255510
6146.100.120.0/2346.100.120.1 to 46.100.121.25446.100.121.255510
6246.100.122.0/2346.100.122.1 to 46.100.123.25446.100.123.255510
6346.100.124.0/2346.100.124.1 to 46.100.125.25446.100.125.255510
6446.100.126.0/2346.100.126.1 to 46.100.127.25446.100.127.255510
6546.100.128.0/2346.100.128.1 to 46.100.129.25446.100.129.255510
6646.100.130.0/2346.100.130.1 to 46.100.131.25446.100.131.255510
6746.100.132.0/2346.100.132.1 to 46.100.133.25446.100.133.255510
6846.100.134.0/2346.100.134.1 to 46.100.135.25446.100.135.255510
6946.100.136.0/2346.100.136.1 to 46.100.137.25446.100.137.255510
7046.100.138.0/2346.100.138.1 to 46.100.139.25446.100.139.255510
7146.100.140.0/2346.100.140.1 to 46.100.141.25446.100.141.255510
7246.100.142.0/2346.100.142.1 to 46.100.143.25446.100.143.255510
7346.100.144.0/2346.100.144.1 to 46.100.145.25446.100.145.255510
7446.100.146.0/2346.100.146.1 to 46.100.147.25446.100.147.255510
7546.100.148.0/2346.100.148.1 to 46.100.149.25446.100.149.255510
7646.100.150.0/2346.100.150.1 to 46.100.151.25446.100.151.255510
7746.100.152.0/2346.100.152.1 to 46.100.153.25446.100.153.255510
7846.100.154.0/2346.100.154.1 to 46.100.155.25446.100.155.255510
7946.100.156.0/2346.100.156.1 to 46.100.157.25446.100.157.255510
8046.100.158.0/2346.100.158.1 to 46.100.159.25446.100.159.255510
8146.100.160.0/2346.100.160.1 to 46.100.161.25446.100.161.255510
8246.100.162.0/2346.100.162.1 to 46.100.163.25446.100.163.255510
8346.100.164.0/2346.100.164.1 to 46.100.165.25446.100.165.255510
8446.100.166.0/2346.100.166.1 to 46.100.167.25446.100.167.255510
8546.100.168.0/2346.100.168.1 to 46.100.169.25446.100.169.255510
8646.100.170.0/2346.100.170.1 to 46.100.171.25446.100.171.255510
8746.100.172.0/2346.100.172.1 to 46.100.173.25446.100.173.255510
8846.100.174.0/2346.100.174.1 to 46.100.175.25446.100.175.255510
8946.100.176.0/2346.100.176.1 to 46.100.177.25446.100.177.255510
9046.100.178.0/2346.100.178.1 to 46.100.179.25446.100.179.255510
9146.100.180.0/2346.100.180.1 to 46.100.181.25446.100.181.255510
9246.100.182.0/2346.100.182.1 to 46.100.183.25446.100.183.255510
9346.100.184.0/2346.100.184.1 to 46.100.185.25446.100.185.255510
9446.100.186.0/2346.100.186.1 to 46.100.187.25446.100.187.255510
9546.100.188.0/2346.100.188.1 to 46.100.189.25446.100.189.255510
9646.100.190.0/2346.100.190.1 to 46.100.191.25446.100.191.255510
9746.100.192.0/2346.100.192.1 to 46.100.193.25446.100.193.255510
9846.100.194.0/2346.100.194.1 to 46.100.195.25446.100.195.255510
9946.100.196.0/2346.100.196.1 to 46.100.197.25446.100.197.255510
10046.100.198.0/2346.100.198.1 to 46.100.199.25446.100.199.255510
10146.100.200.0/2346.100.200.1 to 46.100.201.25446.100.201.255510
10246.100.202.0/2346.100.202.1 to 46.100.203.25446.100.203.255510
10346.100.204.0/2346.100.204.1 to 46.100.205.25446.100.205.255510
10446.100.206.0/2346.100.206.1 to 46.100.207.25446.100.207.255510
10546.100.208.0/2346.100.208.1 to 46.100.209.25446.100.209.255510
10646.100.210.0/2346.100.210.1 to 46.100.211.25446.100.211.255510
10746.100.212.0/2346.100.212.1 to 46.100.213.25446.100.213.255510
10846.100.214.0/2346.100.214.1 to 46.100.215.25446.100.215.255510
10946.100.216.0/2346.100.216.1 to 46.100.217.25446.100.217.255510
11046.100.218.0/2346.100.218.1 to 46.100.219.25446.100.219.255510
11146.100.220.0/2346.100.220.1 to 46.100.221.25446.100.221.255510
11246.100.222.0/2346.100.222.1 to 46.100.223.25446.100.223.255510
11346.100.224.0/2346.100.224.1 to 46.100.225.25446.100.225.255510
11446.100.226.0/2346.100.226.1 to 46.100.227.25446.100.227.255510
11546.100.228.0/2346.100.228.1 to 46.100.229.25446.100.229.255510
11646.100.230.0/2346.100.230.1 to 46.100.231.25446.100.231.255510
11746.100.232.0/2346.100.232.1 to 46.100.233.25446.100.233.255510
11846.100.234.0/2346.100.234.1 to 46.100.235.25446.100.235.255510
11946.100.236.0/2346.100.236.1 to 46.100.237.25446.100.237.255510
12046.100.238.0/2346.100.238.1 to 46.100.239.25446.100.239.255510
12146.100.240.0/2346.100.240.1 to 46.100.241.25446.100.241.255510
12246.100.242.0/2346.100.242.1 to 46.100.243.25446.100.243.255510
12346.100.244.0/2346.100.244.1 to 46.100.245.25446.100.245.255510
12446.100.246.0/2346.100.246.1 to 46.100.247.25446.100.247.255510
12546.100.248.0/2346.100.248.1 to 46.100.249.25446.100.249.255510
12646.100.250.0/2346.100.250.1 to 46.100.251.25446.100.251.255510
12746.100.252.0/2346.100.252.1 to 46.100.253.25446.100.253.255510
12846.100.254.0/2346.100.254.1 to 46.100.255.25446.100.255.255510
12946.101.0.0/2346.101.0.1 to 46.101.1.25446.101.1.255510
13046.101.2.0/2346.101.2.1 to 46.101.3.25446.101.3.255510
13146.101.4.0/2346.101.4.1 to 46.101.5.25446.101.5.255510
13246.101.6.0/2346.101.6.1 to 46.101.7.25446.101.7.255510
13346.101.8.0/2346.101.8.1 to 46.101.9.25446.101.9.255510
13446.101.10.0/2346.101.10.1 to 46.101.11.25446.101.11.255510
13546.101.12.0/2346.101.12.1 to 46.101.13.25446.101.13.255510
13646.101.14.0/2346.101.14.1 to 46.101.15.25446.101.15.255510
13746.101.16.0/2346.101.16.1 to 46.101.17.25446.101.17.255510
13846.101.18.0/2346.101.18.1 to 46.101.19.25446.101.19.255510
13946.101.20.0/2346.101.20.1 to 46.101.21.25446.101.21.255510
14046.101.22.0/2346.101.22.1 to 46.101.23.25446.101.23.255510
14146.101.24.0/2346.101.24.1 to 46.101.25.25446.101.25.255510
14246.101.26.0/2346.101.26.1 to 46.101.27.25446.101.27.255510
14346.101.28.0/2346.101.28.1 to 46.101.29.25446.101.29.255510
14446.101.30.0/2346.101.30.1 to 46.101.31.25446.101.31.255510
14546.101.32.0/2346.101.32.1 to 46.101.33.25446.101.33.255510
14646.101.34.0/2346.101.34.1 to 46.101.35.25446.101.35.255510
14746.101.36.0/2346.101.36.1 to 46.101.37.25446.101.37.255510
14846.101.38.0/2346.101.38.1 to 46.101.39.25446.101.39.255510
14946.101.40.0/2346.101.40.1 to 46.101.41.25446.101.41.255510
15046.101.42.0/2346.101.42.1 to 46.101.43.25446.101.43.255510
15146.101.44.0/2346.101.44.1 to 46.101.45.25446.101.45.255510
15246.101.46.0/2346.101.46.1 to 46.101.47.25446.101.47.255510
15346.101.48.0/2346.101.48.1 to 46.101.49.25446.101.49.255510
15446.101.50.0/2346.101.50.1 to 46.101.51.25446.101.51.255510
15546.101.52.0/2346.101.52.1 to 46.101.53.25446.101.53.255510
15646.101.54.0/2346.101.54.1 to 46.101.55.25446.101.55.255510
15746.101.56.0/2346.101.56.1 to 46.101.57.25446.101.57.255510
15846.101.58.0/2346.101.58.1 to 46.101.59.25446.101.59.255510
15946.101.60.0/2346.101.60.1 to 46.101.61.25446.101.61.255510
16046.101.62.0/2346.101.62.1 to 46.101.63.25446.101.63.255510
16146.101.64.0/2346.101.64.1 to 46.101.65.25446.101.65.255510
16246.101.66.0/2346.101.66.1 to 46.101.67.25446.101.67.255510
16346.101.68.0/2346.101.68.1 to 46.101.69.25446.101.69.255510
16446.101.70.0/2346.101.70.1 to 46.101.71.25446.101.71.255510
16546.101.72.0/2346.101.72.1 to 46.101.73.25446.101.73.255510
16646.101.74.0/2346.101.74.1 to 46.101.75.25446.101.75.255510
16746.101.76.0/2346.101.76.1 to 46.101.77.25446.101.77.255510
16846.101.78.0/2346.101.78.1 to 46.101.79.25446.101.79.255510
16946.101.80.0/2346.101.80.1 to 46.101.81.25446.101.81.255510
17046.101.82.0/2346.101.82.1 to 46.101.83.25446.101.83.255510
17146.101.84.0/2346.101.84.1 to 46.101.85.25446.101.85.255510
17246.101.86.0/2346.101.86.1 to 46.101.87.25446.101.87.255510
17346.101.88.0/2346.101.88.1 to 46.101.89.25446.101.89.255510
17446.101.90.0/2346.101.90.1 to 46.101.91.25446.101.91.255510
17546.101.92.0/2346.101.92.1 to 46.101.93.25446.101.93.255510
17646.101.94.0/2346.101.94.1 to 46.101.95.25446.101.95.255510
17746.101.96.0/2346.101.96.1 to 46.101.97.25446.101.97.255510
17846.101.98.0/2346.101.98.1 to 46.101.99.25446.101.99.255510
17946.101.100.0/2346.101.100.1 to 46.101.101.25446.101.101.255510
18046.101.102.0/2346.101.102.1 to 46.101.103.25446.101.103.255510
18146.101.104.0/2346.101.104.1 to 46.101.105.25446.101.105.255510
18246.101.106.0/2346.101.106.1 to 46.101.107.25446.101.107.255510
18346.101.108.0/2346.101.108.1 to 46.101.109.25446.101.109.255510
18446.101.110.0/2346.101.110.1 to 46.101.111.25446.101.111.255510
18546.101.112.0/2346.101.112.1 to 46.101.113.25446.101.113.255510
18646.101.114.0/2346.101.114.1 to 46.101.115.25446.101.115.255510
18746.101.116.0/2346.101.116.1 to 46.101.117.25446.101.117.255510
18846.101.118.0/2346.101.118.1 to 46.101.119.25446.101.119.255510
18946.101.120.0/2346.101.120.1 to 46.101.121.25446.101.121.255510
19046.101.122.0/2346.101.122.1 to 46.101.123.25446.101.123.255510
19146.101.124.0/2346.101.124.1 to 46.101.125.25446.101.125.255510
19246.101.126.0/2346.101.126.1 to 46.101.127.25446.101.127.255510
19346.101.128.0/2346.101.128.1 to 46.101.129.25446.101.129.255510
19446.101.130.0/2346.101.130.1 to 46.101.131.25446.101.131.255510
19546.101.132.0/2346.101.132.1 to 46.101.133.25446.101.133.255510
19646.101.134.0/2346.101.134.1 to 46.101.135.25446.101.135.255510
19746.101.136.0/2346.101.136.1 to 46.101.137.25446.101.137.255510
19846.101.138.0/2346.101.138.1 to 46.101.139.25446.101.139.255510
19946.101.140.0/2346.101.140.1 to 46.101.141.25446.101.141.255510
20046.101.142.0/2346.101.142.1 to 46.101.143.25446.101.143.255510
20146.101.144.0/2346.101.144.1 to 46.101.145.25446.101.145.255510
20246.101.146.0/2346.101.146.1 to 46.101.147.25446.101.147.255510
20346.101.148.0/2346.101.148.1 to 46.101.149.25446.101.149.255510
20446.101.150.0/2346.101.150.1 to 46.101.151.25446.101.151.255510
20546.101.152.0/2346.101.152.1 to 46.101.153.25446.101.153.255510
20646.101.154.0/2346.101.154.1 to 46.101.155.25446.101.155.255510
20746.101.156.0/2346.101.156.1 to 46.101.157.25446.101.157.255510
20846.101.158.0/2346.101.158.1 to 46.101.159.25446.101.159.255510
20946.101.160.0/2346.101.160.1 to 46.101.161.25446.101.161.255510
21046.101.162.0/2346.101.162.1 to 46.101.163.25446.101.163.255510
21146.101.164.0/2346.101.164.1 to 46.101.165.25446.101.165.255510
21246.101.166.0/2346.101.166.1 to 46.101.167.25446.101.167.255510
21346.101.168.0/2346.101.168.1 to 46.101.169.25446.101.169.255510
21446.101.170.0/2346.101.170.1 to 46.101.171.25446.101.171.255510
21546.101.172.0/2346.101.172.1 to 46.101.173.25446.101.173.255510
21646.101.174.0/2346.101.174.1 to 46.101.175.25446.101.175.255510
21746.101.176.0/2346.101.176.1 to 46.101.177.25446.101.177.255510
21846.101.178.0/2346.101.178.1 to 46.101.179.25446.101.179.255510
21946.101.180.0/2346.101.180.1 to 46.101.181.25446.101.181.255510
22046.101.182.0/2346.101.182.1 to 46.101.183.25446.101.183.255510
22146.101.184.0/2346.101.184.1 to 46.101.185.25446.101.185.255510
22246.101.186.0/2346.101.186.1 to 46.101.187.25446.101.187.255510
22346.101.188.0/2346.101.188.1 to 46.101.189.25446.101.189.255510
22446.101.190.0/2346.101.190.1 to 46.101.191.25446.101.191.255510
22546.101.192.0/2346.101.192.1 to 46.101.193.25446.101.193.255510
22646.101.194.0/2346.101.194.1 to 46.101.195.25446.101.195.255510
22746.101.196.0/2346.101.196.1 to 46.101.197.25446.101.197.255510
22846.101.198.0/2346.101.198.1 to 46.101.199.25446.101.199.255510
22946.101.200.0/2346.101.200.1 to 46.101.201.25446.101.201.255510
23046.101.202.0/2346.101.202.1 to 46.101.203.25446.101.203.255510
23146.101.204.0/2346.101.204.1 to 46.101.205.25446.101.205.255510
23246.101.206.0/2346.101.206.1 to 46.101.207.25446.101.207.255510
23346.101.208.0/2346.101.208.1 to 46.101.209.25446.101.209.255510
23446.101.210.0/2346.101.210.1 to 46.101.211.25446.101.211.255510
23546.101.212.0/2346.101.212.1 to 46.101.213.25446.101.213.255510
23646.101.214.0/2346.101.214.1 to 46.101.215.25446.101.215.255510
23746.101.216.0/2346.101.216.1 to 46.101.217.25446.101.217.255510
23846.101.218.0/2346.101.218.1 to 46.101.219.25446.101.219.255510
23946.101.220.0/2346.101.220.1 to 46.101.221.25446.101.221.255510
24046.101.222.0/2346.101.222.1 to 46.101.223.25446.101.223.255510
24146.101.224.0/2346.101.224.1 to 46.101.225.25446.101.225.255510
24246.101.226.0/2346.101.226.1 to 46.101.227.25446.101.227.255510
24346.101.228.0/2346.101.228.1 to 46.101.229.25446.101.229.255510
24446.101.230.0/2346.101.230.1 to 46.101.231.25446.101.231.255510
24546.101.232.0/2346.101.232.1 to 46.101.233.25446.101.233.255510
24646.101.234.0/2346.101.234.1 to 46.101.235.25446.101.235.255510
24746.101.236.0/2346.101.236.1 to 46.101.237.25446.101.237.255510
24846.101.238.0/2346.101.238.1 to 46.101.239.25446.101.239.255510
24946.101.240.0/2346.101.240.1 to 46.101.241.25446.101.241.255510
25046.101.242.0/2346.101.242.1 to 46.101.243.25446.101.243.255510
25146.101.244.0/2346.101.244.1 to 46.101.245.25446.101.245.255510
25246.101.246.0/2346.101.246.1 to 46.101.247.25446.101.247.255510
25346.101.248.0/2346.101.248.1 to 46.101.249.25446.101.249.255510
25446.101.250.0/2346.101.250.1 to 46.101.251.25446.101.251.255510
25546.101.252.0/2346.101.252.1 to 46.101.253.25446.101.253.255510
25646.101.254.0/2346.101.254.1 to 46.101.255.25446.101.255.255510

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.