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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.

Network46.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
46.0.0.0
Broadcast address
46.255.255.255
First usable
46.0.0.1
Last usable
46.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 2E000000 · Integer 771751936 to 788529151
Reverse DNS zone
46.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101110..00000000.00000000.0000000046.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network00101110..00000000.00000000.0000000046.0.0.0
Broadcast00101110..11111111.11111111.1111111146.255.255.255
Split into smaller subnets/19
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

46.0.0.0/8 makes 2,048 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
146.0.0.0/1946.0.0.1 to 46.0.31.25446.0.31.2558,190
246.0.32.0/1946.0.32.1 to 46.0.63.25446.0.63.2558,190
346.0.64.0/1946.0.64.1 to 46.0.95.25446.0.95.2558,190
446.0.96.0/1946.0.96.1 to 46.0.127.25446.0.127.2558,190
546.0.128.0/1946.0.128.1 to 46.0.159.25446.0.159.2558,190
646.0.160.0/1946.0.160.1 to 46.0.191.25446.0.191.2558,190
746.0.192.0/1946.0.192.1 to 46.0.223.25446.0.223.2558,190
846.0.224.0/1946.0.224.1 to 46.0.255.25446.0.255.2558,190
946.1.0.0/1946.1.0.1 to 46.1.31.25446.1.31.2558,190
1046.1.32.0/1946.1.32.1 to 46.1.63.25446.1.63.2558,190
1146.1.64.0/1946.1.64.1 to 46.1.95.25446.1.95.2558,190
1246.1.96.0/1946.1.96.1 to 46.1.127.25446.1.127.2558,190
1346.1.128.0/1946.1.128.1 to 46.1.159.25446.1.159.2558,190
1446.1.160.0/1946.1.160.1 to 46.1.191.25446.1.191.2558,190
1546.1.192.0/1946.1.192.1 to 46.1.223.25446.1.223.2558,190
1646.1.224.0/1946.1.224.1 to 46.1.255.25446.1.255.2558,190
1746.2.0.0/1946.2.0.1 to 46.2.31.25446.2.31.2558,190
1846.2.32.0/1946.2.32.1 to 46.2.63.25446.2.63.2558,190
1946.2.64.0/1946.2.64.1 to 46.2.95.25446.2.95.2558,190
2046.2.96.0/1946.2.96.1 to 46.2.127.25446.2.127.2558,190
2146.2.128.0/1946.2.128.1 to 46.2.159.25446.2.159.2558,190
2246.2.160.0/1946.2.160.1 to 46.2.191.25446.2.191.2558,190
2346.2.192.0/1946.2.192.1 to 46.2.223.25446.2.223.2558,190
2446.2.224.0/1946.2.224.1 to 46.2.255.25446.2.255.2558,190
2546.3.0.0/1946.3.0.1 to 46.3.31.25446.3.31.2558,190
2646.3.32.0/1946.3.32.1 to 46.3.63.25446.3.63.2558,190
2746.3.64.0/1946.3.64.1 to 46.3.95.25446.3.95.2558,190
2846.3.96.0/1946.3.96.1 to 46.3.127.25446.3.127.2558,190
2946.3.128.0/1946.3.128.1 to 46.3.159.25446.3.159.2558,190
3046.3.160.0/1946.3.160.1 to 46.3.191.25446.3.191.2558,190
3146.3.192.0/1946.3.192.1 to 46.3.223.25446.3.223.2558,190
3246.3.224.0/1946.3.224.1 to 46.3.255.25446.3.255.2558,190
3346.4.0.0/1946.4.0.1 to 46.4.31.25446.4.31.2558,190
3446.4.32.0/1946.4.32.1 to 46.4.63.25446.4.63.2558,190
3546.4.64.0/1946.4.64.1 to 46.4.95.25446.4.95.2558,190
3646.4.96.0/1946.4.96.1 to 46.4.127.25446.4.127.2558,190
3746.4.128.0/1946.4.128.1 to 46.4.159.25446.4.159.2558,190
3846.4.160.0/1946.4.160.1 to 46.4.191.25446.4.191.2558,190
3946.4.192.0/1946.4.192.1 to 46.4.223.25446.4.223.2558,190
4046.4.224.0/1946.4.224.1 to 46.4.255.25446.4.255.2558,190
4146.5.0.0/1946.5.0.1 to 46.5.31.25446.5.31.2558,190
4246.5.32.0/1946.5.32.1 to 46.5.63.25446.5.63.2558,190
4346.5.64.0/1946.5.64.1 to 46.5.95.25446.5.95.2558,190
4446.5.96.0/1946.5.96.1 to 46.5.127.25446.5.127.2558,190
4546.5.128.0/1946.5.128.1 to 46.5.159.25446.5.159.2558,190
4646.5.160.0/1946.5.160.1 to 46.5.191.25446.5.191.2558,190
4746.5.192.0/1946.5.192.1 to 46.5.223.25446.5.223.2558,190
4846.5.224.0/1946.5.224.1 to 46.5.255.25446.5.255.2558,190
4946.6.0.0/1946.6.0.1 to 46.6.31.25446.6.31.2558,190
5046.6.32.0/1946.6.32.1 to 46.6.63.25446.6.63.2558,190
5146.6.64.0/1946.6.64.1 to 46.6.95.25446.6.95.2558,190
5246.6.96.0/1946.6.96.1 to 46.6.127.25446.6.127.2558,190
5346.6.128.0/1946.6.128.1 to 46.6.159.25446.6.159.2558,190
5446.6.160.0/1946.6.160.1 to 46.6.191.25446.6.191.2558,190
5546.6.192.0/1946.6.192.1 to 46.6.223.25446.6.223.2558,190
5646.6.224.0/1946.6.224.1 to 46.6.255.25446.6.255.2558,190
5746.7.0.0/1946.7.0.1 to 46.7.31.25446.7.31.2558,190
5846.7.32.0/1946.7.32.1 to 46.7.63.25446.7.63.2558,190
5946.7.64.0/1946.7.64.1 to 46.7.95.25446.7.95.2558,190
6046.7.96.0/1946.7.96.1 to 46.7.127.25446.7.127.2558,190
6146.7.128.0/1946.7.128.1 to 46.7.159.25446.7.159.2558,190
6246.7.160.0/1946.7.160.1 to 46.7.191.25446.7.191.2558,190
6346.7.192.0/1946.7.192.1 to 46.7.223.25446.7.223.2558,190
6446.7.224.0/1946.7.224.1 to 46.7.255.25446.7.255.2558,190
6546.8.0.0/1946.8.0.1 to 46.8.31.25446.8.31.2558,190
6646.8.32.0/1946.8.32.1 to 46.8.63.25446.8.63.2558,190
6746.8.64.0/1946.8.64.1 to 46.8.95.25446.8.95.2558,190
6846.8.96.0/1946.8.96.1 to 46.8.127.25446.8.127.2558,190
6946.8.128.0/1946.8.128.1 to 46.8.159.25446.8.159.2558,190
7046.8.160.0/1946.8.160.1 to 46.8.191.25446.8.191.2558,190
7146.8.192.0/1946.8.192.1 to 46.8.223.25446.8.223.2558,190
7246.8.224.0/1946.8.224.1 to 46.8.255.25446.8.255.2558,190
7346.9.0.0/1946.9.0.1 to 46.9.31.25446.9.31.2558,190
7446.9.32.0/1946.9.32.1 to 46.9.63.25446.9.63.2558,190
7546.9.64.0/1946.9.64.1 to 46.9.95.25446.9.95.2558,190
7646.9.96.0/1946.9.96.1 to 46.9.127.25446.9.127.2558,190
7746.9.128.0/1946.9.128.1 to 46.9.159.25446.9.159.2558,190
7846.9.160.0/1946.9.160.1 to 46.9.191.25446.9.191.2558,190
7946.9.192.0/1946.9.192.1 to 46.9.223.25446.9.223.2558,190
8046.9.224.0/1946.9.224.1 to 46.9.255.25446.9.255.2558,190
8146.10.0.0/1946.10.0.1 to 46.10.31.25446.10.31.2558,190
8246.10.32.0/1946.10.32.1 to 46.10.63.25446.10.63.2558,190
8346.10.64.0/1946.10.64.1 to 46.10.95.25446.10.95.2558,190
8446.10.96.0/1946.10.96.1 to 46.10.127.25446.10.127.2558,190
8546.10.128.0/1946.10.128.1 to 46.10.159.25446.10.159.2558,190
8646.10.160.0/1946.10.160.1 to 46.10.191.25446.10.191.2558,190
8746.10.192.0/1946.10.192.1 to 46.10.223.25446.10.223.2558,190
8846.10.224.0/1946.10.224.1 to 46.10.255.25446.10.255.2558,190
8946.11.0.0/1946.11.0.1 to 46.11.31.25446.11.31.2558,190
9046.11.32.0/1946.11.32.1 to 46.11.63.25446.11.63.2558,190
9146.11.64.0/1946.11.64.1 to 46.11.95.25446.11.95.2558,190
9246.11.96.0/1946.11.96.1 to 46.11.127.25446.11.127.2558,190
9346.11.128.0/1946.11.128.1 to 46.11.159.25446.11.159.2558,190
9446.11.160.0/1946.11.160.1 to 46.11.191.25446.11.191.2558,190
9546.11.192.0/1946.11.192.1 to 46.11.223.25446.11.223.2558,190
9646.11.224.0/1946.11.224.1 to 46.11.255.25446.11.255.2558,190
9746.12.0.0/1946.12.0.1 to 46.12.31.25446.12.31.2558,190
9846.12.32.0/1946.12.32.1 to 46.12.63.25446.12.63.2558,190
9946.12.64.0/1946.12.64.1 to 46.12.95.25446.12.95.2558,190
10046.12.96.0/1946.12.96.1 to 46.12.127.25446.12.127.2558,190
10146.12.128.0/1946.12.128.1 to 46.12.159.25446.12.159.2558,190
10246.12.160.0/1946.12.160.1 to 46.12.191.25446.12.191.2558,190
10346.12.192.0/1946.12.192.1 to 46.12.223.25446.12.223.2558,190
10446.12.224.0/1946.12.224.1 to 46.12.255.25446.12.255.2558,190
10546.13.0.0/1946.13.0.1 to 46.13.31.25446.13.31.2558,190
10646.13.32.0/1946.13.32.1 to 46.13.63.25446.13.63.2558,190
10746.13.64.0/1946.13.64.1 to 46.13.95.25446.13.95.2558,190
10846.13.96.0/1946.13.96.1 to 46.13.127.25446.13.127.2558,190
10946.13.128.0/1946.13.128.1 to 46.13.159.25446.13.159.2558,190
11046.13.160.0/1946.13.160.1 to 46.13.191.25446.13.191.2558,190
11146.13.192.0/1946.13.192.1 to 46.13.223.25446.13.223.2558,190
11246.13.224.0/1946.13.224.1 to 46.13.255.25446.13.255.2558,190
11346.14.0.0/1946.14.0.1 to 46.14.31.25446.14.31.2558,190
11446.14.32.0/1946.14.32.1 to 46.14.63.25446.14.63.2558,190
11546.14.64.0/1946.14.64.1 to 46.14.95.25446.14.95.2558,190
11646.14.96.0/1946.14.96.1 to 46.14.127.25446.14.127.2558,190
11746.14.128.0/1946.14.128.1 to 46.14.159.25446.14.159.2558,190
11846.14.160.0/1946.14.160.1 to 46.14.191.25446.14.191.2558,190
11946.14.192.0/1946.14.192.1 to 46.14.223.25446.14.223.2558,190
12046.14.224.0/1946.14.224.1 to 46.14.255.25446.14.255.2558,190
12146.15.0.0/1946.15.0.1 to 46.15.31.25446.15.31.2558,190
12246.15.32.0/1946.15.32.1 to 46.15.63.25446.15.63.2558,190
12346.15.64.0/1946.15.64.1 to 46.15.95.25446.15.95.2558,190
12446.15.96.0/1946.15.96.1 to 46.15.127.25446.15.127.2558,190
12546.15.128.0/1946.15.128.1 to 46.15.159.25446.15.159.2558,190
12646.15.160.0/1946.15.160.1 to 46.15.191.25446.15.191.2558,190
12746.15.192.0/1946.15.192.1 to 46.15.223.25446.15.223.2558,190
12846.15.224.0/1946.15.224.1 to 46.15.255.25446.15.255.2558,190
12946.16.0.0/1946.16.0.1 to 46.16.31.25446.16.31.2558,190
13046.16.32.0/1946.16.32.1 to 46.16.63.25446.16.63.2558,190
13146.16.64.0/1946.16.64.1 to 46.16.95.25446.16.95.2558,190
13246.16.96.0/1946.16.96.1 to 46.16.127.25446.16.127.2558,190
13346.16.128.0/1946.16.128.1 to 46.16.159.25446.16.159.2558,190
13446.16.160.0/1946.16.160.1 to 46.16.191.25446.16.191.2558,190
13546.16.192.0/1946.16.192.1 to 46.16.223.25446.16.223.2558,190
13646.16.224.0/1946.16.224.1 to 46.16.255.25446.16.255.2558,190
13746.17.0.0/1946.17.0.1 to 46.17.31.25446.17.31.2558,190
13846.17.32.0/1946.17.32.1 to 46.17.63.25446.17.63.2558,190
13946.17.64.0/1946.17.64.1 to 46.17.95.25446.17.95.2558,190
14046.17.96.0/1946.17.96.1 to 46.17.127.25446.17.127.2558,190
14146.17.128.0/1946.17.128.1 to 46.17.159.25446.17.159.2558,190
14246.17.160.0/1946.17.160.1 to 46.17.191.25446.17.191.2558,190
14346.17.192.0/1946.17.192.1 to 46.17.223.25446.17.223.2558,190
14446.17.224.0/1946.17.224.1 to 46.17.255.25446.17.255.2558,190
14546.18.0.0/1946.18.0.1 to 46.18.31.25446.18.31.2558,190
14646.18.32.0/1946.18.32.1 to 46.18.63.25446.18.63.2558,190
14746.18.64.0/1946.18.64.1 to 46.18.95.25446.18.95.2558,190
14846.18.96.0/1946.18.96.1 to 46.18.127.25446.18.127.2558,190
14946.18.128.0/1946.18.128.1 to 46.18.159.25446.18.159.2558,190
15046.18.160.0/1946.18.160.1 to 46.18.191.25446.18.191.2558,190
15146.18.192.0/1946.18.192.1 to 46.18.223.25446.18.223.2558,190
15246.18.224.0/1946.18.224.1 to 46.18.255.25446.18.255.2558,190
15346.19.0.0/1946.19.0.1 to 46.19.31.25446.19.31.2558,190
15446.19.32.0/1946.19.32.1 to 46.19.63.25446.19.63.2558,190
15546.19.64.0/1946.19.64.1 to 46.19.95.25446.19.95.2558,190
15646.19.96.0/1946.19.96.1 to 46.19.127.25446.19.127.2558,190
15746.19.128.0/1946.19.128.1 to 46.19.159.25446.19.159.2558,190
15846.19.160.0/1946.19.160.1 to 46.19.191.25446.19.191.2558,190
15946.19.192.0/1946.19.192.1 to 46.19.223.25446.19.223.2558,190
16046.19.224.0/1946.19.224.1 to 46.19.255.25446.19.255.2558,190
16146.20.0.0/1946.20.0.1 to 46.20.31.25446.20.31.2558,190
16246.20.32.0/1946.20.32.1 to 46.20.63.25446.20.63.2558,190
16346.20.64.0/1946.20.64.1 to 46.20.95.25446.20.95.2558,190
16446.20.96.0/1946.20.96.1 to 46.20.127.25446.20.127.2558,190
16546.20.128.0/1946.20.128.1 to 46.20.159.25446.20.159.2558,190
16646.20.160.0/1946.20.160.1 to 46.20.191.25446.20.191.2558,190
16746.20.192.0/1946.20.192.1 to 46.20.223.25446.20.223.2558,190
16846.20.224.0/1946.20.224.1 to 46.20.255.25446.20.255.2558,190
16946.21.0.0/1946.21.0.1 to 46.21.31.25446.21.31.2558,190
17046.21.32.0/1946.21.32.1 to 46.21.63.25446.21.63.2558,190
17146.21.64.0/1946.21.64.1 to 46.21.95.25446.21.95.2558,190
17246.21.96.0/1946.21.96.1 to 46.21.127.25446.21.127.2558,190
17346.21.128.0/1946.21.128.1 to 46.21.159.25446.21.159.2558,190
17446.21.160.0/1946.21.160.1 to 46.21.191.25446.21.191.2558,190
17546.21.192.0/1946.21.192.1 to 46.21.223.25446.21.223.2558,190
17646.21.224.0/1946.21.224.1 to 46.21.255.25446.21.255.2558,190
17746.22.0.0/1946.22.0.1 to 46.22.31.25446.22.31.2558,190
17846.22.32.0/1946.22.32.1 to 46.22.63.25446.22.63.2558,190
17946.22.64.0/1946.22.64.1 to 46.22.95.25446.22.95.2558,190
18046.22.96.0/1946.22.96.1 to 46.22.127.25446.22.127.2558,190
18146.22.128.0/1946.22.128.1 to 46.22.159.25446.22.159.2558,190
18246.22.160.0/1946.22.160.1 to 46.22.191.25446.22.191.2558,190
18346.22.192.0/1946.22.192.1 to 46.22.223.25446.22.223.2558,190
18446.22.224.0/1946.22.224.1 to 46.22.255.25446.22.255.2558,190
18546.23.0.0/1946.23.0.1 to 46.23.31.25446.23.31.2558,190
18646.23.32.0/1946.23.32.1 to 46.23.63.25446.23.63.2558,190
18746.23.64.0/1946.23.64.1 to 46.23.95.25446.23.95.2558,190
18846.23.96.0/1946.23.96.1 to 46.23.127.25446.23.127.2558,190
18946.23.128.0/1946.23.128.1 to 46.23.159.25446.23.159.2558,190
19046.23.160.0/1946.23.160.1 to 46.23.191.25446.23.191.2558,190
19146.23.192.0/1946.23.192.1 to 46.23.223.25446.23.223.2558,190
19246.23.224.0/1946.23.224.1 to 46.23.255.25446.23.255.2558,190
19346.24.0.0/1946.24.0.1 to 46.24.31.25446.24.31.2558,190
19446.24.32.0/1946.24.32.1 to 46.24.63.25446.24.63.2558,190
19546.24.64.0/1946.24.64.1 to 46.24.95.25446.24.95.2558,190
19646.24.96.0/1946.24.96.1 to 46.24.127.25446.24.127.2558,190
19746.24.128.0/1946.24.128.1 to 46.24.159.25446.24.159.2558,190
19846.24.160.0/1946.24.160.1 to 46.24.191.25446.24.191.2558,190
19946.24.192.0/1946.24.192.1 to 46.24.223.25446.24.223.2558,190
20046.24.224.0/1946.24.224.1 to 46.24.255.25446.24.255.2558,190
20146.25.0.0/1946.25.0.1 to 46.25.31.25446.25.31.2558,190
20246.25.32.0/1946.25.32.1 to 46.25.63.25446.25.63.2558,190
20346.25.64.0/1946.25.64.1 to 46.25.95.25446.25.95.2558,190
20446.25.96.0/1946.25.96.1 to 46.25.127.25446.25.127.2558,190
20546.25.128.0/1946.25.128.1 to 46.25.159.25446.25.159.2558,190
20646.25.160.0/1946.25.160.1 to 46.25.191.25446.25.191.2558,190
20746.25.192.0/1946.25.192.1 to 46.25.223.25446.25.223.2558,190
20846.25.224.0/1946.25.224.1 to 46.25.255.25446.25.255.2558,190
20946.26.0.0/1946.26.0.1 to 46.26.31.25446.26.31.2558,190
21046.26.32.0/1946.26.32.1 to 46.26.63.25446.26.63.2558,190
21146.26.64.0/1946.26.64.1 to 46.26.95.25446.26.95.2558,190
21246.26.96.0/1946.26.96.1 to 46.26.127.25446.26.127.2558,190
21346.26.128.0/1946.26.128.1 to 46.26.159.25446.26.159.2558,190
21446.26.160.0/1946.26.160.1 to 46.26.191.25446.26.191.2558,190
21546.26.192.0/1946.26.192.1 to 46.26.223.25446.26.223.2558,190
21646.26.224.0/1946.26.224.1 to 46.26.255.25446.26.255.2558,190
21746.27.0.0/1946.27.0.1 to 46.27.31.25446.27.31.2558,190
21846.27.32.0/1946.27.32.1 to 46.27.63.25446.27.63.2558,190
21946.27.64.0/1946.27.64.1 to 46.27.95.25446.27.95.2558,190
22046.27.96.0/1946.27.96.1 to 46.27.127.25446.27.127.2558,190
22146.27.128.0/1946.27.128.1 to 46.27.159.25446.27.159.2558,190
22246.27.160.0/1946.27.160.1 to 46.27.191.25446.27.191.2558,190
22346.27.192.0/1946.27.192.1 to 46.27.223.25446.27.223.2558,190
22446.27.224.0/1946.27.224.1 to 46.27.255.25446.27.255.2558,190
22546.28.0.0/1946.28.0.1 to 46.28.31.25446.28.31.2558,190
22646.28.32.0/1946.28.32.1 to 46.28.63.25446.28.63.2558,190
22746.28.64.0/1946.28.64.1 to 46.28.95.25446.28.95.2558,190
22846.28.96.0/1946.28.96.1 to 46.28.127.25446.28.127.2558,190
22946.28.128.0/1946.28.128.1 to 46.28.159.25446.28.159.2558,190
23046.28.160.0/1946.28.160.1 to 46.28.191.25446.28.191.2558,190
23146.28.192.0/1946.28.192.1 to 46.28.223.25446.28.223.2558,190
23246.28.224.0/1946.28.224.1 to 46.28.255.25446.28.255.2558,190
23346.29.0.0/1946.29.0.1 to 46.29.31.25446.29.31.2558,190
23446.29.32.0/1946.29.32.1 to 46.29.63.25446.29.63.2558,190
23546.29.64.0/1946.29.64.1 to 46.29.95.25446.29.95.2558,190
23646.29.96.0/1946.29.96.1 to 46.29.127.25446.29.127.2558,190
23746.29.128.0/1946.29.128.1 to 46.29.159.25446.29.159.2558,190
23846.29.160.0/1946.29.160.1 to 46.29.191.25446.29.191.2558,190
23946.29.192.0/1946.29.192.1 to 46.29.223.25446.29.223.2558,190
24046.29.224.0/1946.29.224.1 to 46.29.255.25446.29.255.2558,190
24146.30.0.0/1946.30.0.1 to 46.30.31.25446.30.31.2558,190
24246.30.32.0/1946.30.32.1 to 46.30.63.25446.30.63.2558,190
24346.30.64.0/1946.30.64.1 to 46.30.95.25446.30.95.2558,190
24446.30.96.0/1946.30.96.1 to 46.30.127.25446.30.127.2558,190
24546.30.128.0/1946.30.128.1 to 46.30.159.25446.30.159.2558,190
24646.30.160.0/1946.30.160.1 to 46.30.191.25446.30.191.2558,190
24746.30.192.0/1946.30.192.1 to 46.30.223.25446.30.223.2558,190
24846.30.224.0/1946.30.224.1 to 46.30.255.25446.30.255.2558,190
24946.31.0.0/1946.31.0.1 to 46.31.31.25446.31.31.2558,190
25046.31.32.0/1946.31.32.1 to 46.31.63.25446.31.63.2558,190
25146.31.64.0/1946.31.64.1 to 46.31.95.25446.31.95.2558,190
25246.31.96.0/1946.31.96.1 to 46.31.127.25446.31.127.2558,190
25346.31.128.0/1946.31.128.1 to 46.31.159.25446.31.159.2558,190
25446.31.160.0/1946.31.160.1 to 46.31.191.25446.31.191.2558,190
25546.31.192.0/1946.31.192.1 to 46.31.223.25446.31.223.2558,190
25646.31.224.0/1946.31.224.1 to 46.31.255.25446.31.255.2558,190

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.