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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.

Network46.128.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
46.128.0.0
Broadcast address
46.191.255.255
First usable
46.128.0.1
Last usable
46.191.255.254
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 2E800000 · Integer 780140544 to 784334847
Reverse DNS zones
128.46.in-addr.arpa
129.46.in-addr.arpa
130.46.in-addr.arpa
131.46.in-addr.arpa
132.46.in-addr.arpa
133.46.in-addr.arpa
134.46.in-addr.arpa
135.46.in-addr.arpa
136.46.in-addr.arpa
137.46.in-addr.arpa
138.46.in-addr.arpa
139.46.in-addr.arpa
140.46.in-addr.arpa
141.46.in-addr.arpa
142.46.in-addr.arpa
143.46.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
Address00101110.10000000.00000000.0000000046.128.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00101110.10000000.00000000.0000000046.128.0.0
Broadcast00101110.10111111.11111111.1111111146.191.255.255
Split into smaller subnets/18
/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)

46.128.0.0/10 makes 256 subnets of /18.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
146.128.0.0/1846.128.0.1 to 46.128.63.25446.128.63.25516,382
246.128.64.0/1846.128.64.1 to 46.128.127.25446.128.127.25516,382
346.128.128.0/1846.128.128.1 to 46.128.191.25446.128.191.25516,382
446.128.192.0/1846.128.192.1 to 46.128.255.25446.128.255.25516,382
546.129.0.0/1846.129.0.1 to 46.129.63.25446.129.63.25516,382
646.129.64.0/1846.129.64.1 to 46.129.127.25446.129.127.25516,382
746.129.128.0/1846.129.128.1 to 46.129.191.25446.129.191.25516,382
846.129.192.0/1846.129.192.1 to 46.129.255.25446.129.255.25516,382
946.130.0.0/1846.130.0.1 to 46.130.63.25446.130.63.25516,382
1046.130.64.0/1846.130.64.1 to 46.130.127.25446.130.127.25516,382
1146.130.128.0/1846.130.128.1 to 46.130.191.25446.130.191.25516,382
1246.130.192.0/1846.130.192.1 to 46.130.255.25446.130.255.25516,382
1346.131.0.0/1846.131.0.1 to 46.131.63.25446.131.63.25516,382
1446.131.64.0/1846.131.64.1 to 46.131.127.25446.131.127.25516,382
1546.131.128.0/1846.131.128.1 to 46.131.191.25446.131.191.25516,382
1646.131.192.0/1846.131.192.1 to 46.131.255.25446.131.255.25516,382
1746.132.0.0/1846.132.0.1 to 46.132.63.25446.132.63.25516,382
1846.132.64.0/1846.132.64.1 to 46.132.127.25446.132.127.25516,382
1946.132.128.0/1846.132.128.1 to 46.132.191.25446.132.191.25516,382
2046.132.192.0/1846.132.192.1 to 46.132.255.25446.132.255.25516,382
2146.133.0.0/1846.133.0.1 to 46.133.63.25446.133.63.25516,382
2246.133.64.0/1846.133.64.1 to 46.133.127.25446.133.127.25516,382
2346.133.128.0/1846.133.128.1 to 46.133.191.25446.133.191.25516,382
2446.133.192.0/1846.133.192.1 to 46.133.255.25446.133.255.25516,382
2546.134.0.0/1846.134.0.1 to 46.134.63.25446.134.63.25516,382
2646.134.64.0/1846.134.64.1 to 46.134.127.25446.134.127.25516,382
2746.134.128.0/1846.134.128.1 to 46.134.191.25446.134.191.25516,382
2846.134.192.0/1846.134.192.1 to 46.134.255.25446.134.255.25516,382
2946.135.0.0/1846.135.0.1 to 46.135.63.25446.135.63.25516,382
3046.135.64.0/1846.135.64.1 to 46.135.127.25446.135.127.25516,382
3146.135.128.0/1846.135.128.1 to 46.135.191.25446.135.191.25516,382
3246.135.192.0/1846.135.192.1 to 46.135.255.25446.135.255.25516,382
3346.136.0.0/1846.136.0.1 to 46.136.63.25446.136.63.25516,382
3446.136.64.0/1846.136.64.1 to 46.136.127.25446.136.127.25516,382
3546.136.128.0/1846.136.128.1 to 46.136.191.25446.136.191.25516,382
3646.136.192.0/1846.136.192.1 to 46.136.255.25446.136.255.25516,382
3746.137.0.0/1846.137.0.1 to 46.137.63.25446.137.63.25516,382
3846.137.64.0/1846.137.64.1 to 46.137.127.25446.137.127.25516,382
3946.137.128.0/1846.137.128.1 to 46.137.191.25446.137.191.25516,382
4046.137.192.0/1846.137.192.1 to 46.137.255.25446.137.255.25516,382
4146.138.0.0/1846.138.0.1 to 46.138.63.25446.138.63.25516,382
4246.138.64.0/1846.138.64.1 to 46.138.127.25446.138.127.25516,382
4346.138.128.0/1846.138.128.1 to 46.138.191.25446.138.191.25516,382
4446.138.192.0/1846.138.192.1 to 46.138.255.25446.138.255.25516,382
4546.139.0.0/1846.139.0.1 to 46.139.63.25446.139.63.25516,382
4646.139.64.0/1846.139.64.1 to 46.139.127.25446.139.127.25516,382
4746.139.128.0/1846.139.128.1 to 46.139.191.25446.139.191.25516,382
4846.139.192.0/1846.139.192.1 to 46.139.255.25446.139.255.25516,382
4946.140.0.0/1846.140.0.1 to 46.140.63.25446.140.63.25516,382
5046.140.64.0/1846.140.64.1 to 46.140.127.25446.140.127.25516,382
5146.140.128.0/1846.140.128.1 to 46.140.191.25446.140.191.25516,382
5246.140.192.0/1846.140.192.1 to 46.140.255.25446.140.255.25516,382
5346.141.0.0/1846.141.0.1 to 46.141.63.25446.141.63.25516,382
5446.141.64.0/1846.141.64.1 to 46.141.127.25446.141.127.25516,382
5546.141.128.0/1846.141.128.1 to 46.141.191.25446.141.191.25516,382
5646.141.192.0/1846.141.192.1 to 46.141.255.25446.141.255.25516,382
5746.142.0.0/1846.142.0.1 to 46.142.63.25446.142.63.25516,382
5846.142.64.0/1846.142.64.1 to 46.142.127.25446.142.127.25516,382
5946.142.128.0/1846.142.128.1 to 46.142.191.25446.142.191.25516,382
6046.142.192.0/1846.142.192.1 to 46.142.255.25446.142.255.25516,382
6146.143.0.0/1846.143.0.1 to 46.143.63.25446.143.63.25516,382
6246.143.64.0/1846.143.64.1 to 46.143.127.25446.143.127.25516,382
6346.143.128.0/1846.143.128.1 to 46.143.191.25446.143.191.25516,382
6446.143.192.0/1846.143.192.1 to 46.143.255.25446.143.255.25516,382
6546.144.0.0/1846.144.0.1 to 46.144.63.25446.144.63.25516,382
6646.144.64.0/1846.144.64.1 to 46.144.127.25446.144.127.25516,382
6746.144.128.0/1846.144.128.1 to 46.144.191.25446.144.191.25516,382
6846.144.192.0/1846.144.192.1 to 46.144.255.25446.144.255.25516,382
6946.145.0.0/1846.145.0.1 to 46.145.63.25446.145.63.25516,382
7046.145.64.0/1846.145.64.1 to 46.145.127.25446.145.127.25516,382
7146.145.128.0/1846.145.128.1 to 46.145.191.25446.145.191.25516,382
7246.145.192.0/1846.145.192.1 to 46.145.255.25446.145.255.25516,382
7346.146.0.0/1846.146.0.1 to 46.146.63.25446.146.63.25516,382
7446.146.64.0/1846.146.64.1 to 46.146.127.25446.146.127.25516,382
7546.146.128.0/1846.146.128.1 to 46.146.191.25446.146.191.25516,382
7646.146.192.0/1846.146.192.1 to 46.146.255.25446.146.255.25516,382
7746.147.0.0/1846.147.0.1 to 46.147.63.25446.147.63.25516,382
7846.147.64.0/1846.147.64.1 to 46.147.127.25446.147.127.25516,382
7946.147.128.0/1846.147.128.1 to 46.147.191.25446.147.191.25516,382
8046.147.192.0/1846.147.192.1 to 46.147.255.25446.147.255.25516,382
8146.148.0.0/1846.148.0.1 to 46.148.63.25446.148.63.25516,382
8246.148.64.0/1846.148.64.1 to 46.148.127.25446.148.127.25516,382
8346.148.128.0/1846.148.128.1 to 46.148.191.25446.148.191.25516,382
8446.148.192.0/1846.148.192.1 to 46.148.255.25446.148.255.25516,382
8546.149.0.0/1846.149.0.1 to 46.149.63.25446.149.63.25516,382
8646.149.64.0/1846.149.64.1 to 46.149.127.25446.149.127.25516,382
8746.149.128.0/1846.149.128.1 to 46.149.191.25446.149.191.25516,382
8846.149.192.0/1846.149.192.1 to 46.149.255.25446.149.255.25516,382
8946.150.0.0/1846.150.0.1 to 46.150.63.25446.150.63.25516,382
9046.150.64.0/1846.150.64.1 to 46.150.127.25446.150.127.25516,382
9146.150.128.0/1846.150.128.1 to 46.150.191.25446.150.191.25516,382
9246.150.192.0/1846.150.192.1 to 46.150.255.25446.150.255.25516,382
9346.151.0.0/1846.151.0.1 to 46.151.63.25446.151.63.25516,382
9446.151.64.0/1846.151.64.1 to 46.151.127.25446.151.127.25516,382
9546.151.128.0/1846.151.128.1 to 46.151.191.25446.151.191.25516,382
9646.151.192.0/1846.151.192.1 to 46.151.255.25446.151.255.25516,382
9746.152.0.0/1846.152.0.1 to 46.152.63.25446.152.63.25516,382
9846.152.64.0/1846.152.64.1 to 46.152.127.25446.152.127.25516,382
9946.152.128.0/1846.152.128.1 to 46.152.191.25446.152.191.25516,382
10046.152.192.0/1846.152.192.1 to 46.152.255.25446.152.255.25516,382
10146.153.0.0/1846.153.0.1 to 46.153.63.25446.153.63.25516,382
10246.153.64.0/1846.153.64.1 to 46.153.127.25446.153.127.25516,382
10346.153.128.0/1846.153.128.1 to 46.153.191.25446.153.191.25516,382
10446.153.192.0/1846.153.192.1 to 46.153.255.25446.153.255.25516,382
10546.154.0.0/1846.154.0.1 to 46.154.63.25446.154.63.25516,382
10646.154.64.0/1846.154.64.1 to 46.154.127.25446.154.127.25516,382
10746.154.128.0/1846.154.128.1 to 46.154.191.25446.154.191.25516,382
10846.154.192.0/1846.154.192.1 to 46.154.255.25446.154.255.25516,382
10946.155.0.0/1846.155.0.1 to 46.155.63.25446.155.63.25516,382
11046.155.64.0/1846.155.64.1 to 46.155.127.25446.155.127.25516,382
11146.155.128.0/1846.155.128.1 to 46.155.191.25446.155.191.25516,382
11246.155.192.0/1846.155.192.1 to 46.155.255.25446.155.255.25516,382
11346.156.0.0/1846.156.0.1 to 46.156.63.25446.156.63.25516,382
11446.156.64.0/1846.156.64.1 to 46.156.127.25446.156.127.25516,382
11546.156.128.0/1846.156.128.1 to 46.156.191.25446.156.191.25516,382
11646.156.192.0/1846.156.192.1 to 46.156.255.25446.156.255.25516,382
11746.157.0.0/1846.157.0.1 to 46.157.63.25446.157.63.25516,382
11846.157.64.0/1846.157.64.1 to 46.157.127.25446.157.127.25516,382
11946.157.128.0/1846.157.128.1 to 46.157.191.25446.157.191.25516,382
12046.157.192.0/1846.157.192.1 to 46.157.255.25446.157.255.25516,382
12146.158.0.0/1846.158.0.1 to 46.158.63.25446.158.63.25516,382
12246.158.64.0/1846.158.64.1 to 46.158.127.25446.158.127.25516,382
12346.158.128.0/1846.158.128.1 to 46.158.191.25446.158.191.25516,382
12446.158.192.0/1846.158.192.1 to 46.158.255.25446.158.255.25516,382
12546.159.0.0/1846.159.0.1 to 46.159.63.25446.159.63.25516,382
12646.159.64.0/1846.159.64.1 to 46.159.127.25446.159.127.25516,382
12746.159.128.0/1846.159.128.1 to 46.159.191.25446.159.191.25516,382
12846.159.192.0/1846.159.192.1 to 46.159.255.25446.159.255.25516,382
12946.160.0.0/1846.160.0.1 to 46.160.63.25446.160.63.25516,382
13046.160.64.0/1846.160.64.1 to 46.160.127.25446.160.127.25516,382
13146.160.128.0/1846.160.128.1 to 46.160.191.25446.160.191.25516,382
13246.160.192.0/1846.160.192.1 to 46.160.255.25446.160.255.25516,382
13346.161.0.0/1846.161.0.1 to 46.161.63.25446.161.63.25516,382
13446.161.64.0/1846.161.64.1 to 46.161.127.25446.161.127.25516,382
13546.161.128.0/1846.161.128.1 to 46.161.191.25446.161.191.25516,382
13646.161.192.0/1846.161.192.1 to 46.161.255.25446.161.255.25516,382
13746.162.0.0/1846.162.0.1 to 46.162.63.25446.162.63.25516,382
13846.162.64.0/1846.162.64.1 to 46.162.127.25446.162.127.25516,382
13946.162.128.0/1846.162.128.1 to 46.162.191.25446.162.191.25516,382
14046.162.192.0/1846.162.192.1 to 46.162.255.25446.162.255.25516,382
14146.163.0.0/1846.163.0.1 to 46.163.63.25446.163.63.25516,382
14246.163.64.0/1846.163.64.1 to 46.163.127.25446.163.127.25516,382
14346.163.128.0/1846.163.128.1 to 46.163.191.25446.163.191.25516,382
14446.163.192.0/1846.163.192.1 to 46.163.255.25446.163.255.25516,382
14546.164.0.0/1846.164.0.1 to 46.164.63.25446.164.63.25516,382
14646.164.64.0/1846.164.64.1 to 46.164.127.25446.164.127.25516,382
14746.164.128.0/1846.164.128.1 to 46.164.191.25446.164.191.25516,382
14846.164.192.0/1846.164.192.1 to 46.164.255.25446.164.255.25516,382
14946.165.0.0/1846.165.0.1 to 46.165.63.25446.165.63.25516,382
15046.165.64.0/1846.165.64.1 to 46.165.127.25446.165.127.25516,382
15146.165.128.0/1846.165.128.1 to 46.165.191.25446.165.191.25516,382
15246.165.192.0/1846.165.192.1 to 46.165.255.25446.165.255.25516,382
15346.166.0.0/1846.166.0.1 to 46.166.63.25446.166.63.25516,382
15446.166.64.0/1846.166.64.1 to 46.166.127.25446.166.127.25516,382
15546.166.128.0/1846.166.128.1 to 46.166.191.25446.166.191.25516,382
15646.166.192.0/1846.166.192.1 to 46.166.255.25446.166.255.25516,382
15746.167.0.0/1846.167.0.1 to 46.167.63.25446.167.63.25516,382
15846.167.64.0/1846.167.64.1 to 46.167.127.25446.167.127.25516,382
15946.167.128.0/1846.167.128.1 to 46.167.191.25446.167.191.25516,382
16046.167.192.0/1846.167.192.1 to 46.167.255.25446.167.255.25516,382
16146.168.0.0/1846.168.0.1 to 46.168.63.25446.168.63.25516,382
16246.168.64.0/1846.168.64.1 to 46.168.127.25446.168.127.25516,382
16346.168.128.0/1846.168.128.1 to 46.168.191.25446.168.191.25516,382
16446.168.192.0/1846.168.192.1 to 46.168.255.25446.168.255.25516,382
16546.169.0.0/1846.169.0.1 to 46.169.63.25446.169.63.25516,382
16646.169.64.0/1846.169.64.1 to 46.169.127.25446.169.127.25516,382
16746.169.128.0/1846.169.128.1 to 46.169.191.25446.169.191.25516,382
16846.169.192.0/1846.169.192.1 to 46.169.255.25446.169.255.25516,382
16946.170.0.0/1846.170.0.1 to 46.170.63.25446.170.63.25516,382
17046.170.64.0/1846.170.64.1 to 46.170.127.25446.170.127.25516,382
17146.170.128.0/1846.170.128.1 to 46.170.191.25446.170.191.25516,382
17246.170.192.0/1846.170.192.1 to 46.170.255.25446.170.255.25516,382
17346.171.0.0/1846.171.0.1 to 46.171.63.25446.171.63.25516,382
17446.171.64.0/1846.171.64.1 to 46.171.127.25446.171.127.25516,382
17546.171.128.0/1846.171.128.1 to 46.171.191.25446.171.191.25516,382
17646.171.192.0/1846.171.192.1 to 46.171.255.25446.171.255.25516,382
17746.172.0.0/1846.172.0.1 to 46.172.63.25446.172.63.25516,382
17846.172.64.0/1846.172.64.1 to 46.172.127.25446.172.127.25516,382
17946.172.128.0/1846.172.128.1 to 46.172.191.25446.172.191.25516,382
18046.172.192.0/1846.172.192.1 to 46.172.255.25446.172.255.25516,382
18146.173.0.0/1846.173.0.1 to 46.173.63.25446.173.63.25516,382
18246.173.64.0/1846.173.64.1 to 46.173.127.25446.173.127.25516,382
18346.173.128.0/1846.173.128.1 to 46.173.191.25446.173.191.25516,382
18446.173.192.0/1846.173.192.1 to 46.173.255.25446.173.255.25516,382
18546.174.0.0/1846.174.0.1 to 46.174.63.25446.174.63.25516,382
18646.174.64.0/1846.174.64.1 to 46.174.127.25446.174.127.25516,382
18746.174.128.0/1846.174.128.1 to 46.174.191.25446.174.191.25516,382
18846.174.192.0/1846.174.192.1 to 46.174.255.25446.174.255.25516,382
18946.175.0.0/1846.175.0.1 to 46.175.63.25446.175.63.25516,382
19046.175.64.0/1846.175.64.1 to 46.175.127.25446.175.127.25516,382
19146.175.128.0/1846.175.128.1 to 46.175.191.25446.175.191.25516,382
19246.175.192.0/1846.175.192.1 to 46.175.255.25446.175.255.25516,382
19346.176.0.0/1846.176.0.1 to 46.176.63.25446.176.63.25516,382
19446.176.64.0/1846.176.64.1 to 46.176.127.25446.176.127.25516,382
19546.176.128.0/1846.176.128.1 to 46.176.191.25446.176.191.25516,382
19646.176.192.0/1846.176.192.1 to 46.176.255.25446.176.255.25516,382
19746.177.0.0/1846.177.0.1 to 46.177.63.25446.177.63.25516,382
19846.177.64.0/1846.177.64.1 to 46.177.127.25446.177.127.25516,382
19946.177.128.0/1846.177.128.1 to 46.177.191.25446.177.191.25516,382
20046.177.192.0/1846.177.192.1 to 46.177.255.25446.177.255.25516,382
20146.178.0.0/1846.178.0.1 to 46.178.63.25446.178.63.25516,382
20246.178.64.0/1846.178.64.1 to 46.178.127.25446.178.127.25516,382
20346.178.128.0/1846.178.128.1 to 46.178.191.25446.178.191.25516,382
20446.178.192.0/1846.178.192.1 to 46.178.255.25446.178.255.25516,382
20546.179.0.0/1846.179.0.1 to 46.179.63.25446.179.63.25516,382
20646.179.64.0/1846.179.64.1 to 46.179.127.25446.179.127.25516,382
20746.179.128.0/1846.179.128.1 to 46.179.191.25446.179.191.25516,382
20846.179.192.0/1846.179.192.1 to 46.179.255.25446.179.255.25516,382
20946.180.0.0/1846.180.0.1 to 46.180.63.25446.180.63.25516,382
21046.180.64.0/1846.180.64.1 to 46.180.127.25446.180.127.25516,382
21146.180.128.0/1846.180.128.1 to 46.180.191.25446.180.191.25516,382
21246.180.192.0/1846.180.192.1 to 46.180.255.25446.180.255.25516,382
21346.181.0.0/1846.181.0.1 to 46.181.63.25446.181.63.25516,382
21446.181.64.0/1846.181.64.1 to 46.181.127.25446.181.127.25516,382
21546.181.128.0/1846.181.128.1 to 46.181.191.25446.181.191.25516,382
21646.181.192.0/1846.181.192.1 to 46.181.255.25446.181.255.25516,382
21746.182.0.0/1846.182.0.1 to 46.182.63.25446.182.63.25516,382
21846.182.64.0/1846.182.64.1 to 46.182.127.25446.182.127.25516,382
21946.182.128.0/1846.182.128.1 to 46.182.191.25446.182.191.25516,382
22046.182.192.0/1846.182.192.1 to 46.182.255.25446.182.255.25516,382
22146.183.0.0/1846.183.0.1 to 46.183.63.25446.183.63.25516,382
22246.183.64.0/1846.183.64.1 to 46.183.127.25446.183.127.25516,382
22346.183.128.0/1846.183.128.1 to 46.183.191.25446.183.191.25516,382
22446.183.192.0/1846.183.192.1 to 46.183.255.25446.183.255.25516,382
22546.184.0.0/1846.184.0.1 to 46.184.63.25446.184.63.25516,382
22646.184.64.0/1846.184.64.1 to 46.184.127.25446.184.127.25516,382
22746.184.128.0/1846.184.128.1 to 46.184.191.25446.184.191.25516,382
22846.184.192.0/1846.184.192.1 to 46.184.255.25446.184.255.25516,382
22946.185.0.0/1846.185.0.1 to 46.185.63.25446.185.63.25516,382
23046.185.64.0/1846.185.64.1 to 46.185.127.25446.185.127.25516,382
23146.185.128.0/1846.185.128.1 to 46.185.191.25446.185.191.25516,382
23246.185.192.0/1846.185.192.1 to 46.185.255.25446.185.255.25516,382
23346.186.0.0/1846.186.0.1 to 46.186.63.25446.186.63.25516,382
23446.186.64.0/1846.186.64.1 to 46.186.127.25446.186.127.25516,382
23546.186.128.0/1846.186.128.1 to 46.186.191.25446.186.191.25516,382
23646.186.192.0/1846.186.192.1 to 46.186.255.25446.186.255.25516,382
23746.187.0.0/1846.187.0.1 to 46.187.63.25446.187.63.25516,382
23846.187.64.0/1846.187.64.1 to 46.187.127.25446.187.127.25516,382
23946.187.128.0/1846.187.128.1 to 46.187.191.25446.187.191.25516,382
24046.187.192.0/1846.187.192.1 to 46.187.255.25446.187.255.25516,382
24146.188.0.0/1846.188.0.1 to 46.188.63.25446.188.63.25516,382
24246.188.64.0/1846.188.64.1 to 46.188.127.25446.188.127.25516,382
24346.188.128.0/1846.188.128.1 to 46.188.191.25446.188.191.25516,382
24446.188.192.0/1846.188.192.1 to 46.188.255.25446.188.255.25516,382
24546.189.0.0/1846.189.0.1 to 46.189.63.25446.189.63.25516,382
24646.189.64.0/1846.189.64.1 to 46.189.127.25446.189.127.25516,382
24746.189.128.0/1846.189.128.1 to 46.189.191.25446.189.191.25516,382
24846.189.192.0/1846.189.192.1 to 46.189.255.25446.189.255.25516,382
24946.190.0.0/1846.190.0.1 to 46.190.63.25446.190.63.25516,382
25046.190.64.0/1846.190.64.1 to 46.190.127.25446.190.127.25516,382
25146.190.128.0/1846.190.128.1 to 46.190.191.25446.190.191.25516,382
25246.190.192.0/1846.190.192.1 to 46.190.255.25446.190.255.25516,382
25346.191.0.0/1846.191.0.1 to 46.191.63.25446.191.63.25516,382
25446.191.64.0/1846.191.64.1 to 46.191.127.25446.191.127.25516,382
25546.191.128.0/1846.191.128.1 to 46.191.191.25446.191.191.25516,382
25646.191.192.0/1846.191.192.1 to 46.191.255.25446.191.255.25516,382

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.