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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.

Network46.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
46.0.0.0
Broadcast address
46.127.255.255
First usable
46.0.0.1
Last usable
46.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 2E000000 · Integer 771751936 to 780140543
Reverse DNS zones
0.46.in-addr.arpa
1.46.in-addr.arpa
2.46.in-addr.arpa
3.46.in-addr.arpa
4.46.in-addr.arpa
5.46.in-addr.arpa
6.46.in-addr.arpa
7.46.in-addr.arpa
8.46.in-addr.arpa
9.46.in-addr.arpa
10.46.in-addr.arpa
11.46.in-addr.arpa
12.46.in-addr.arpa
13.46.in-addr.arpa
14.46.in-addr.arpa
15.46.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101110.00000000.00000000.0000000046.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network00101110.00000000.00000000.0000000046.0.0.0
Broadcast00101110.01111111.11111111.1111111146.127.255.255
Split into smaller subnets/20
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

46.0.0.0/9 makes 2,048 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
146.0.0.0/2046.0.0.1 to 46.0.15.25446.0.15.2554,094
246.0.16.0/2046.0.16.1 to 46.0.31.25446.0.31.2554,094
346.0.32.0/2046.0.32.1 to 46.0.47.25446.0.47.2554,094
446.0.48.0/2046.0.48.1 to 46.0.63.25446.0.63.2554,094
546.0.64.0/2046.0.64.1 to 46.0.79.25446.0.79.2554,094
646.0.80.0/2046.0.80.1 to 46.0.95.25446.0.95.2554,094
746.0.96.0/2046.0.96.1 to 46.0.111.25446.0.111.2554,094
846.0.112.0/2046.0.112.1 to 46.0.127.25446.0.127.2554,094
946.0.128.0/2046.0.128.1 to 46.0.143.25446.0.143.2554,094
1046.0.144.0/2046.0.144.1 to 46.0.159.25446.0.159.2554,094
1146.0.160.0/2046.0.160.1 to 46.0.175.25446.0.175.2554,094
1246.0.176.0/2046.0.176.1 to 46.0.191.25446.0.191.2554,094
1346.0.192.0/2046.0.192.1 to 46.0.207.25446.0.207.2554,094
1446.0.208.0/2046.0.208.1 to 46.0.223.25446.0.223.2554,094
1546.0.224.0/2046.0.224.1 to 46.0.239.25446.0.239.2554,094
1646.0.240.0/2046.0.240.1 to 46.0.255.25446.0.255.2554,094
1746.1.0.0/2046.1.0.1 to 46.1.15.25446.1.15.2554,094
1846.1.16.0/2046.1.16.1 to 46.1.31.25446.1.31.2554,094
1946.1.32.0/2046.1.32.1 to 46.1.47.25446.1.47.2554,094
2046.1.48.0/2046.1.48.1 to 46.1.63.25446.1.63.2554,094
2146.1.64.0/2046.1.64.1 to 46.1.79.25446.1.79.2554,094
2246.1.80.0/2046.1.80.1 to 46.1.95.25446.1.95.2554,094
2346.1.96.0/2046.1.96.1 to 46.1.111.25446.1.111.2554,094
2446.1.112.0/2046.1.112.1 to 46.1.127.25446.1.127.2554,094
2546.1.128.0/2046.1.128.1 to 46.1.143.25446.1.143.2554,094
2646.1.144.0/2046.1.144.1 to 46.1.159.25446.1.159.2554,094
2746.1.160.0/2046.1.160.1 to 46.1.175.25446.1.175.2554,094
2846.1.176.0/2046.1.176.1 to 46.1.191.25446.1.191.2554,094
2946.1.192.0/2046.1.192.1 to 46.1.207.25446.1.207.2554,094
3046.1.208.0/2046.1.208.1 to 46.1.223.25446.1.223.2554,094
3146.1.224.0/2046.1.224.1 to 46.1.239.25446.1.239.2554,094
3246.1.240.0/2046.1.240.1 to 46.1.255.25446.1.255.2554,094
3346.2.0.0/2046.2.0.1 to 46.2.15.25446.2.15.2554,094
3446.2.16.0/2046.2.16.1 to 46.2.31.25446.2.31.2554,094
3546.2.32.0/2046.2.32.1 to 46.2.47.25446.2.47.2554,094
3646.2.48.0/2046.2.48.1 to 46.2.63.25446.2.63.2554,094
3746.2.64.0/2046.2.64.1 to 46.2.79.25446.2.79.2554,094
3846.2.80.0/2046.2.80.1 to 46.2.95.25446.2.95.2554,094
3946.2.96.0/2046.2.96.1 to 46.2.111.25446.2.111.2554,094
4046.2.112.0/2046.2.112.1 to 46.2.127.25446.2.127.2554,094
4146.2.128.0/2046.2.128.1 to 46.2.143.25446.2.143.2554,094
4246.2.144.0/2046.2.144.1 to 46.2.159.25446.2.159.2554,094
4346.2.160.0/2046.2.160.1 to 46.2.175.25446.2.175.2554,094
4446.2.176.0/2046.2.176.1 to 46.2.191.25446.2.191.2554,094
4546.2.192.0/2046.2.192.1 to 46.2.207.25446.2.207.2554,094
4646.2.208.0/2046.2.208.1 to 46.2.223.25446.2.223.2554,094
4746.2.224.0/2046.2.224.1 to 46.2.239.25446.2.239.2554,094
4846.2.240.0/2046.2.240.1 to 46.2.255.25446.2.255.2554,094
4946.3.0.0/2046.3.0.1 to 46.3.15.25446.3.15.2554,094
5046.3.16.0/2046.3.16.1 to 46.3.31.25446.3.31.2554,094
5146.3.32.0/2046.3.32.1 to 46.3.47.25446.3.47.2554,094
5246.3.48.0/2046.3.48.1 to 46.3.63.25446.3.63.2554,094
5346.3.64.0/2046.3.64.1 to 46.3.79.25446.3.79.2554,094
5446.3.80.0/2046.3.80.1 to 46.3.95.25446.3.95.2554,094
5546.3.96.0/2046.3.96.1 to 46.3.111.25446.3.111.2554,094
5646.3.112.0/2046.3.112.1 to 46.3.127.25446.3.127.2554,094
5746.3.128.0/2046.3.128.1 to 46.3.143.25446.3.143.2554,094
5846.3.144.0/2046.3.144.1 to 46.3.159.25446.3.159.2554,094
5946.3.160.0/2046.3.160.1 to 46.3.175.25446.3.175.2554,094
6046.3.176.0/2046.3.176.1 to 46.3.191.25446.3.191.2554,094
6146.3.192.0/2046.3.192.1 to 46.3.207.25446.3.207.2554,094
6246.3.208.0/2046.3.208.1 to 46.3.223.25446.3.223.2554,094
6346.3.224.0/2046.3.224.1 to 46.3.239.25446.3.239.2554,094
6446.3.240.0/2046.3.240.1 to 46.3.255.25446.3.255.2554,094
6546.4.0.0/2046.4.0.1 to 46.4.15.25446.4.15.2554,094
6646.4.16.0/2046.4.16.1 to 46.4.31.25446.4.31.2554,094
6746.4.32.0/2046.4.32.1 to 46.4.47.25446.4.47.2554,094
6846.4.48.0/2046.4.48.1 to 46.4.63.25446.4.63.2554,094
6946.4.64.0/2046.4.64.1 to 46.4.79.25446.4.79.2554,094
7046.4.80.0/2046.4.80.1 to 46.4.95.25446.4.95.2554,094
7146.4.96.0/2046.4.96.1 to 46.4.111.25446.4.111.2554,094
7246.4.112.0/2046.4.112.1 to 46.4.127.25446.4.127.2554,094
7346.4.128.0/2046.4.128.1 to 46.4.143.25446.4.143.2554,094
7446.4.144.0/2046.4.144.1 to 46.4.159.25446.4.159.2554,094
7546.4.160.0/2046.4.160.1 to 46.4.175.25446.4.175.2554,094
7646.4.176.0/2046.4.176.1 to 46.4.191.25446.4.191.2554,094
7746.4.192.0/2046.4.192.1 to 46.4.207.25446.4.207.2554,094
7846.4.208.0/2046.4.208.1 to 46.4.223.25446.4.223.2554,094
7946.4.224.0/2046.4.224.1 to 46.4.239.25446.4.239.2554,094
8046.4.240.0/2046.4.240.1 to 46.4.255.25446.4.255.2554,094
8146.5.0.0/2046.5.0.1 to 46.5.15.25446.5.15.2554,094
8246.5.16.0/2046.5.16.1 to 46.5.31.25446.5.31.2554,094
8346.5.32.0/2046.5.32.1 to 46.5.47.25446.5.47.2554,094
8446.5.48.0/2046.5.48.1 to 46.5.63.25446.5.63.2554,094
8546.5.64.0/2046.5.64.1 to 46.5.79.25446.5.79.2554,094
8646.5.80.0/2046.5.80.1 to 46.5.95.25446.5.95.2554,094
8746.5.96.0/2046.5.96.1 to 46.5.111.25446.5.111.2554,094
8846.5.112.0/2046.5.112.1 to 46.5.127.25446.5.127.2554,094
8946.5.128.0/2046.5.128.1 to 46.5.143.25446.5.143.2554,094
9046.5.144.0/2046.5.144.1 to 46.5.159.25446.5.159.2554,094
9146.5.160.0/2046.5.160.1 to 46.5.175.25446.5.175.2554,094
9246.5.176.0/2046.5.176.1 to 46.5.191.25446.5.191.2554,094
9346.5.192.0/2046.5.192.1 to 46.5.207.25446.5.207.2554,094
9446.5.208.0/2046.5.208.1 to 46.5.223.25446.5.223.2554,094
9546.5.224.0/2046.5.224.1 to 46.5.239.25446.5.239.2554,094
9646.5.240.0/2046.5.240.1 to 46.5.255.25446.5.255.2554,094
9746.6.0.0/2046.6.0.1 to 46.6.15.25446.6.15.2554,094
9846.6.16.0/2046.6.16.1 to 46.6.31.25446.6.31.2554,094
9946.6.32.0/2046.6.32.1 to 46.6.47.25446.6.47.2554,094
10046.6.48.0/2046.6.48.1 to 46.6.63.25446.6.63.2554,094
10146.6.64.0/2046.6.64.1 to 46.6.79.25446.6.79.2554,094
10246.6.80.0/2046.6.80.1 to 46.6.95.25446.6.95.2554,094
10346.6.96.0/2046.6.96.1 to 46.6.111.25446.6.111.2554,094
10446.6.112.0/2046.6.112.1 to 46.6.127.25446.6.127.2554,094
10546.6.128.0/2046.6.128.1 to 46.6.143.25446.6.143.2554,094
10646.6.144.0/2046.6.144.1 to 46.6.159.25446.6.159.2554,094
10746.6.160.0/2046.6.160.1 to 46.6.175.25446.6.175.2554,094
10846.6.176.0/2046.6.176.1 to 46.6.191.25446.6.191.2554,094
10946.6.192.0/2046.6.192.1 to 46.6.207.25446.6.207.2554,094
11046.6.208.0/2046.6.208.1 to 46.6.223.25446.6.223.2554,094
11146.6.224.0/2046.6.224.1 to 46.6.239.25446.6.239.2554,094
11246.6.240.0/2046.6.240.1 to 46.6.255.25446.6.255.2554,094
11346.7.0.0/2046.7.0.1 to 46.7.15.25446.7.15.2554,094
11446.7.16.0/2046.7.16.1 to 46.7.31.25446.7.31.2554,094
11546.7.32.0/2046.7.32.1 to 46.7.47.25446.7.47.2554,094
11646.7.48.0/2046.7.48.1 to 46.7.63.25446.7.63.2554,094
11746.7.64.0/2046.7.64.1 to 46.7.79.25446.7.79.2554,094
11846.7.80.0/2046.7.80.1 to 46.7.95.25446.7.95.2554,094
11946.7.96.0/2046.7.96.1 to 46.7.111.25446.7.111.2554,094
12046.7.112.0/2046.7.112.1 to 46.7.127.25446.7.127.2554,094
12146.7.128.0/2046.7.128.1 to 46.7.143.25446.7.143.2554,094
12246.7.144.0/2046.7.144.1 to 46.7.159.25446.7.159.2554,094
12346.7.160.0/2046.7.160.1 to 46.7.175.25446.7.175.2554,094
12446.7.176.0/2046.7.176.1 to 46.7.191.25446.7.191.2554,094
12546.7.192.0/2046.7.192.1 to 46.7.207.25446.7.207.2554,094
12646.7.208.0/2046.7.208.1 to 46.7.223.25446.7.223.2554,094
12746.7.224.0/2046.7.224.1 to 46.7.239.25446.7.239.2554,094
12846.7.240.0/2046.7.240.1 to 46.7.255.25446.7.255.2554,094
12946.8.0.0/2046.8.0.1 to 46.8.15.25446.8.15.2554,094
13046.8.16.0/2046.8.16.1 to 46.8.31.25446.8.31.2554,094
13146.8.32.0/2046.8.32.1 to 46.8.47.25446.8.47.2554,094
13246.8.48.0/2046.8.48.1 to 46.8.63.25446.8.63.2554,094
13346.8.64.0/2046.8.64.1 to 46.8.79.25446.8.79.2554,094
13446.8.80.0/2046.8.80.1 to 46.8.95.25446.8.95.2554,094
13546.8.96.0/2046.8.96.1 to 46.8.111.25446.8.111.2554,094
13646.8.112.0/2046.8.112.1 to 46.8.127.25446.8.127.2554,094
13746.8.128.0/2046.8.128.1 to 46.8.143.25446.8.143.2554,094
13846.8.144.0/2046.8.144.1 to 46.8.159.25446.8.159.2554,094
13946.8.160.0/2046.8.160.1 to 46.8.175.25446.8.175.2554,094
14046.8.176.0/2046.8.176.1 to 46.8.191.25446.8.191.2554,094
14146.8.192.0/2046.8.192.1 to 46.8.207.25446.8.207.2554,094
14246.8.208.0/2046.8.208.1 to 46.8.223.25446.8.223.2554,094
14346.8.224.0/2046.8.224.1 to 46.8.239.25446.8.239.2554,094
14446.8.240.0/2046.8.240.1 to 46.8.255.25446.8.255.2554,094
14546.9.0.0/2046.9.0.1 to 46.9.15.25446.9.15.2554,094
14646.9.16.0/2046.9.16.1 to 46.9.31.25446.9.31.2554,094
14746.9.32.0/2046.9.32.1 to 46.9.47.25446.9.47.2554,094
14846.9.48.0/2046.9.48.1 to 46.9.63.25446.9.63.2554,094
14946.9.64.0/2046.9.64.1 to 46.9.79.25446.9.79.2554,094
15046.9.80.0/2046.9.80.1 to 46.9.95.25446.9.95.2554,094
15146.9.96.0/2046.9.96.1 to 46.9.111.25446.9.111.2554,094
15246.9.112.0/2046.9.112.1 to 46.9.127.25446.9.127.2554,094
15346.9.128.0/2046.9.128.1 to 46.9.143.25446.9.143.2554,094
15446.9.144.0/2046.9.144.1 to 46.9.159.25446.9.159.2554,094
15546.9.160.0/2046.9.160.1 to 46.9.175.25446.9.175.2554,094
15646.9.176.0/2046.9.176.1 to 46.9.191.25446.9.191.2554,094
15746.9.192.0/2046.9.192.1 to 46.9.207.25446.9.207.2554,094
15846.9.208.0/2046.9.208.1 to 46.9.223.25446.9.223.2554,094
15946.9.224.0/2046.9.224.1 to 46.9.239.25446.9.239.2554,094
16046.9.240.0/2046.9.240.1 to 46.9.255.25446.9.255.2554,094
16146.10.0.0/2046.10.0.1 to 46.10.15.25446.10.15.2554,094
16246.10.16.0/2046.10.16.1 to 46.10.31.25446.10.31.2554,094
16346.10.32.0/2046.10.32.1 to 46.10.47.25446.10.47.2554,094
16446.10.48.0/2046.10.48.1 to 46.10.63.25446.10.63.2554,094
16546.10.64.0/2046.10.64.1 to 46.10.79.25446.10.79.2554,094
16646.10.80.0/2046.10.80.1 to 46.10.95.25446.10.95.2554,094
16746.10.96.0/2046.10.96.1 to 46.10.111.25446.10.111.2554,094
16846.10.112.0/2046.10.112.1 to 46.10.127.25446.10.127.2554,094
16946.10.128.0/2046.10.128.1 to 46.10.143.25446.10.143.2554,094
17046.10.144.0/2046.10.144.1 to 46.10.159.25446.10.159.2554,094
17146.10.160.0/2046.10.160.1 to 46.10.175.25446.10.175.2554,094
17246.10.176.0/2046.10.176.1 to 46.10.191.25446.10.191.2554,094
17346.10.192.0/2046.10.192.1 to 46.10.207.25446.10.207.2554,094
17446.10.208.0/2046.10.208.1 to 46.10.223.25446.10.223.2554,094
17546.10.224.0/2046.10.224.1 to 46.10.239.25446.10.239.2554,094
17646.10.240.0/2046.10.240.1 to 46.10.255.25446.10.255.2554,094
17746.11.0.0/2046.11.0.1 to 46.11.15.25446.11.15.2554,094
17846.11.16.0/2046.11.16.1 to 46.11.31.25446.11.31.2554,094
17946.11.32.0/2046.11.32.1 to 46.11.47.25446.11.47.2554,094
18046.11.48.0/2046.11.48.1 to 46.11.63.25446.11.63.2554,094
18146.11.64.0/2046.11.64.1 to 46.11.79.25446.11.79.2554,094
18246.11.80.0/2046.11.80.1 to 46.11.95.25446.11.95.2554,094
18346.11.96.0/2046.11.96.1 to 46.11.111.25446.11.111.2554,094
18446.11.112.0/2046.11.112.1 to 46.11.127.25446.11.127.2554,094
18546.11.128.0/2046.11.128.1 to 46.11.143.25446.11.143.2554,094
18646.11.144.0/2046.11.144.1 to 46.11.159.25446.11.159.2554,094
18746.11.160.0/2046.11.160.1 to 46.11.175.25446.11.175.2554,094
18846.11.176.0/2046.11.176.1 to 46.11.191.25446.11.191.2554,094
18946.11.192.0/2046.11.192.1 to 46.11.207.25446.11.207.2554,094
19046.11.208.0/2046.11.208.1 to 46.11.223.25446.11.223.2554,094
19146.11.224.0/2046.11.224.1 to 46.11.239.25446.11.239.2554,094
19246.11.240.0/2046.11.240.1 to 46.11.255.25446.11.255.2554,094
19346.12.0.0/2046.12.0.1 to 46.12.15.25446.12.15.2554,094
19446.12.16.0/2046.12.16.1 to 46.12.31.25446.12.31.2554,094
19546.12.32.0/2046.12.32.1 to 46.12.47.25446.12.47.2554,094
19646.12.48.0/2046.12.48.1 to 46.12.63.25446.12.63.2554,094
19746.12.64.0/2046.12.64.1 to 46.12.79.25446.12.79.2554,094
19846.12.80.0/2046.12.80.1 to 46.12.95.25446.12.95.2554,094
19946.12.96.0/2046.12.96.1 to 46.12.111.25446.12.111.2554,094
20046.12.112.0/2046.12.112.1 to 46.12.127.25446.12.127.2554,094
20146.12.128.0/2046.12.128.1 to 46.12.143.25446.12.143.2554,094
20246.12.144.0/2046.12.144.1 to 46.12.159.25446.12.159.2554,094
20346.12.160.0/2046.12.160.1 to 46.12.175.25446.12.175.2554,094
20446.12.176.0/2046.12.176.1 to 46.12.191.25446.12.191.2554,094
20546.12.192.0/2046.12.192.1 to 46.12.207.25446.12.207.2554,094
20646.12.208.0/2046.12.208.1 to 46.12.223.25446.12.223.2554,094
20746.12.224.0/2046.12.224.1 to 46.12.239.25446.12.239.2554,094
20846.12.240.0/2046.12.240.1 to 46.12.255.25446.12.255.2554,094
20946.13.0.0/2046.13.0.1 to 46.13.15.25446.13.15.2554,094
21046.13.16.0/2046.13.16.1 to 46.13.31.25446.13.31.2554,094
21146.13.32.0/2046.13.32.1 to 46.13.47.25446.13.47.2554,094
21246.13.48.0/2046.13.48.1 to 46.13.63.25446.13.63.2554,094
21346.13.64.0/2046.13.64.1 to 46.13.79.25446.13.79.2554,094
21446.13.80.0/2046.13.80.1 to 46.13.95.25446.13.95.2554,094
21546.13.96.0/2046.13.96.1 to 46.13.111.25446.13.111.2554,094
21646.13.112.0/2046.13.112.1 to 46.13.127.25446.13.127.2554,094
21746.13.128.0/2046.13.128.1 to 46.13.143.25446.13.143.2554,094
21846.13.144.0/2046.13.144.1 to 46.13.159.25446.13.159.2554,094
21946.13.160.0/2046.13.160.1 to 46.13.175.25446.13.175.2554,094
22046.13.176.0/2046.13.176.1 to 46.13.191.25446.13.191.2554,094
22146.13.192.0/2046.13.192.1 to 46.13.207.25446.13.207.2554,094
22246.13.208.0/2046.13.208.1 to 46.13.223.25446.13.223.2554,094
22346.13.224.0/2046.13.224.1 to 46.13.239.25446.13.239.2554,094
22446.13.240.0/2046.13.240.1 to 46.13.255.25446.13.255.2554,094
22546.14.0.0/2046.14.0.1 to 46.14.15.25446.14.15.2554,094
22646.14.16.0/2046.14.16.1 to 46.14.31.25446.14.31.2554,094
22746.14.32.0/2046.14.32.1 to 46.14.47.25446.14.47.2554,094
22846.14.48.0/2046.14.48.1 to 46.14.63.25446.14.63.2554,094
22946.14.64.0/2046.14.64.1 to 46.14.79.25446.14.79.2554,094
23046.14.80.0/2046.14.80.1 to 46.14.95.25446.14.95.2554,094
23146.14.96.0/2046.14.96.1 to 46.14.111.25446.14.111.2554,094
23246.14.112.0/2046.14.112.1 to 46.14.127.25446.14.127.2554,094
23346.14.128.0/2046.14.128.1 to 46.14.143.25446.14.143.2554,094
23446.14.144.0/2046.14.144.1 to 46.14.159.25446.14.159.2554,094
23546.14.160.0/2046.14.160.1 to 46.14.175.25446.14.175.2554,094
23646.14.176.0/2046.14.176.1 to 46.14.191.25446.14.191.2554,094
23746.14.192.0/2046.14.192.1 to 46.14.207.25446.14.207.2554,094
23846.14.208.0/2046.14.208.1 to 46.14.223.25446.14.223.2554,094
23946.14.224.0/2046.14.224.1 to 46.14.239.25446.14.239.2554,094
24046.14.240.0/2046.14.240.1 to 46.14.255.25446.14.255.2554,094
24146.15.0.0/2046.15.0.1 to 46.15.15.25446.15.15.2554,094
24246.15.16.0/2046.15.16.1 to 46.15.31.25446.15.31.2554,094
24346.15.32.0/2046.15.32.1 to 46.15.47.25446.15.47.2554,094
24446.15.48.0/2046.15.48.1 to 46.15.63.25446.15.63.2554,094
24546.15.64.0/2046.15.64.1 to 46.15.79.25446.15.79.2554,094
24646.15.80.0/2046.15.80.1 to 46.15.95.25446.15.95.2554,094
24746.15.96.0/2046.15.96.1 to 46.15.111.25446.15.111.2554,094
24846.15.112.0/2046.15.112.1 to 46.15.127.25446.15.127.2554,094
24946.15.128.0/2046.15.128.1 to 46.15.143.25446.15.143.2554,094
25046.15.144.0/2046.15.144.1 to 46.15.159.25446.15.159.2554,094
25146.15.160.0/2046.15.160.1 to 46.15.175.25446.15.175.2554,094
25246.15.176.0/2046.15.176.1 to 46.15.191.25446.15.191.2554,094
25346.15.192.0/2046.15.192.1 to 46.15.207.25446.15.207.2554,094
25446.15.208.0/2046.15.208.1 to 46.15.223.25446.15.223.2554,094
25546.15.224.0/2046.15.224.1 to 46.15.239.25446.15.239.2554,094
25646.15.240.0/2046.15.240.1 to 46.15.255.25446.15.255.2554,094

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.