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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.

Network80.14.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
80.14.0.0
Broadcast address
80.14.63.255
First usable
80.14.0.1
Last usable
80.14.63.254
Usable hosts
16,382 (16,384 less the network and broadcast addresses)
Subnet mask
255.255.192.0
Wildcard mask
0.0.63.255 (Cisco ACLs, OSPF)
Prefix length
/18
Type
Public public
Old class
A (default /8)
As numbers
Hex 500E0000 · Integer 1343094784 to 1343111167
Reverse DNS zones
0.14.80.in-addr.arpa
1.14.80.in-addr.arpa
2.14.80.in-addr.arpa
3.14.80.in-addr.arpa
4.14.80.in-addr.arpa
5.14.80.in-addr.arpa
6.14.80.in-addr.arpa
7.14.80.in-addr.arpa
8.14.80.in-addr.arpa
9.14.80.in-addr.arpa
10.14.80.in-addr.arpa
11.14.80.in-addr.arpa
12.14.80.in-addr.arpa
13.14.80.in-addr.arpa
14.14.80.in-addr.arpa
15.14.80.in-addr.arpa
and 48 more
/18 is not on a 8-bit boundary, so it takes 64 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010000.00001110.00000000.0000000080.14.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network01010000.00001110.00000000.0000000080.14.0.0
Broadcast01010000.00001110.00111111.1111111180.14.63.255
Split into smaller subnets/27
/19 (2)/20 (4)/21 (8)/22 (16)/23 (32)/24 (64)/25 (128)/26 (256)/27 (512)/28 (1,024)/29 (2,048)/30 (4,096)

80.14.0.0/18 makes 512 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
180.14.0.0/2780.14.0.1 to 80.14.0.3080.14.0.3130
280.14.0.32/2780.14.0.33 to 80.14.0.6280.14.0.6330
380.14.0.64/2780.14.0.65 to 80.14.0.9480.14.0.9530
480.14.0.96/2780.14.0.97 to 80.14.0.12680.14.0.12730
580.14.0.128/2780.14.0.129 to 80.14.0.15880.14.0.15930
680.14.0.160/2780.14.0.161 to 80.14.0.19080.14.0.19130
780.14.0.192/2780.14.0.193 to 80.14.0.22280.14.0.22330
880.14.0.224/2780.14.0.225 to 80.14.0.25480.14.0.25530
980.14.1.0/2780.14.1.1 to 80.14.1.3080.14.1.3130
1080.14.1.32/2780.14.1.33 to 80.14.1.6280.14.1.6330
1180.14.1.64/2780.14.1.65 to 80.14.1.9480.14.1.9530
1280.14.1.96/2780.14.1.97 to 80.14.1.12680.14.1.12730
1380.14.1.128/2780.14.1.129 to 80.14.1.15880.14.1.15930
1480.14.1.160/2780.14.1.161 to 80.14.1.19080.14.1.19130
1580.14.1.192/2780.14.1.193 to 80.14.1.22280.14.1.22330
1680.14.1.224/2780.14.1.225 to 80.14.1.25480.14.1.25530
1780.14.2.0/2780.14.2.1 to 80.14.2.3080.14.2.3130
1880.14.2.32/2780.14.2.33 to 80.14.2.6280.14.2.6330
1980.14.2.64/2780.14.2.65 to 80.14.2.9480.14.2.9530
2080.14.2.96/2780.14.2.97 to 80.14.2.12680.14.2.12730
2180.14.2.128/2780.14.2.129 to 80.14.2.15880.14.2.15930
2280.14.2.160/2780.14.2.161 to 80.14.2.19080.14.2.19130
2380.14.2.192/2780.14.2.193 to 80.14.2.22280.14.2.22330
2480.14.2.224/2780.14.2.225 to 80.14.2.25480.14.2.25530
2580.14.3.0/2780.14.3.1 to 80.14.3.3080.14.3.3130
2680.14.3.32/2780.14.3.33 to 80.14.3.6280.14.3.6330
2780.14.3.64/2780.14.3.65 to 80.14.3.9480.14.3.9530
2880.14.3.96/2780.14.3.97 to 80.14.3.12680.14.3.12730
2980.14.3.128/2780.14.3.129 to 80.14.3.15880.14.3.15930
3080.14.3.160/2780.14.3.161 to 80.14.3.19080.14.3.19130
3180.14.3.192/2780.14.3.193 to 80.14.3.22280.14.3.22330
3280.14.3.224/2780.14.3.225 to 80.14.3.25480.14.3.25530
3380.14.4.0/2780.14.4.1 to 80.14.4.3080.14.4.3130
3480.14.4.32/2780.14.4.33 to 80.14.4.6280.14.4.6330
3580.14.4.64/2780.14.4.65 to 80.14.4.9480.14.4.9530
3680.14.4.96/2780.14.4.97 to 80.14.4.12680.14.4.12730
3780.14.4.128/2780.14.4.129 to 80.14.4.15880.14.4.15930
3880.14.4.160/2780.14.4.161 to 80.14.4.19080.14.4.19130
3980.14.4.192/2780.14.4.193 to 80.14.4.22280.14.4.22330
4080.14.4.224/2780.14.4.225 to 80.14.4.25480.14.4.25530
4180.14.5.0/2780.14.5.1 to 80.14.5.3080.14.5.3130
4280.14.5.32/2780.14.5.33 to 80.14.5.6280.14.5.6330
4380.14.5.64/2780.14.5.65 to 80.14.5.9480.14.5.9530
4480.14.5.96/2780.14.5.97 to 80.14.5.12680.14.5.12730
4580.14.5.128/2780.14.5.129 to 80.14.5.15880.14.5.15930
4680.14.5.160/2780.14.5.161 to 80.14.5.19080.14.5.19130
4780.14.5.192/2780.14.5.193 to 80.14.5.22280.14.5.22330
4880.14.5.224/2780.14.5.225 to 80.14.5.25480.14.5.25530
4980.14.6.0/2780.14.6.1 to 80.14.6.3080.14.6.3130
5080.14.6.32/2780.14.6.33 to 80.14.6.6280.14.6.6330
5180.14.6.64/2780.14.6.65 to 80.14.6.9480.14.6.9530
5280.14.6.96/2780.14.6.97 to 80.14.6.12680.14.6.12730
5380.14.6.128/2780.14.6.129 to 80.14.6.15880.14.6.15930
5480.14.6.160/2780.14.6.161 to 80.14.6.19080.14.6.19130
5580.14.6.192/2780.14.6.193 to 80.14.6.22280.14.6.22330
5680.14.6.224/2780.14.6.225 to 80.14.6.25480.14.6.25530
5780.14.7.0/2780.14.7.1 to 80.14.7.3080.14.7.3130
5880.14.7.32/2780.14.7.33 to 80.14.7.6280.14.7.6330
5980.14.7.64/2780.14.7.65 to 80.14.7.9480.14.7.9530
6080.14.7.96/2780.14.7.97 to 80.14.7.12680.14.7.12730
6180.14.7.128/2780.14.7.129 to 80.14.7.15880.14.7.15930
6280.14.7.160/2780.14.7.161 to 80.14.7.19080.14.7.19130
6380.14.7.192/2780.14.7.193 to 80.14.7.22280.14.7.22330
6480.14.7.224/2780.14.7.225 to 80.14.7.25480.14.7.25530
6580.14.8.0/2780.14.8.1 to 80.14.8.3080.14.8.3130
6680.14.8.32/2780.14.8.33 to 80.14.8.6280.14.8.6330
6780.14.8.64/2780.14.8.65 to 80.14.8.9480.14.8.9530
6880.14.8.96/2780.14.8.97 to 80.14.8.12680.14.8.12730
6980.14.8.128/2780.14.8.129 to 80.14.8.15880.14.8.15930
7080.14.8.160/2780.14.8.161 to 80.14.8.19080.14.8.19130
7180.14.8.192/2780.14.8.193 to 80.14.8.22280.14.8.22330
7280.14.8.224/2780.14.8.225 to 80.14.8.25480.14.8.25530
7380.14.9.0/2780.14.9.1 to 80.14.9.3080.14.9.3130
7480.14.9.32/2780.14.9.33 to 80.14.9.6280.14.9.6330
7580.14.9.64/2780.14.9.65 to 80.14.9.9480.14.9.9530
7680.14.9.96/2780.14.9.97 to 80.14.9.12680.14.9.12730
7780.14.9.128/2780.14.9.129 to 80.14.9.15880.14.9.15930
7880.14.9.160/2780.14.9.161 to 80.14.9.19080.14.9.19130
7980.14.9.192/2780.14.9.193 to 80.14.9.22280.14.9.22330
8080.14.9.224/2780.14.9.225 to 80.14.9.25480.14.9.25530
8180.14.10.0/2780.14.10.1 to 80.14.10.3080.14.10.3130
8280.14.10.32/2780.14.10.33 to 80.14.10.6280.14.10.6330
8380.14.10.64/2780.14.10.65 to 80.14.10.9480.14.10.9530
8480.14.10.96/2780.14.10.97 to 80.14.10.12680.14.10.12730
8580.14.10.128/2780.14.10.129 to 80.14.10.15880.14.10.15930
8680.14.10.160/2780.14.10.161 to 80.14.10.19080.14.10.19130
8780.14.10.192/2780.14.10.193 to 80.14.10.22280.14.10.22330
8880.14.10.224/2780.14.10.225 to 80.14.10.25480.14.10.25530
8980.14.11.0/2780.14.11.1 to 80.14.11.3080.14.11.3130
9080.14.11.32/2780.14.11.33 to 80.14.11.6280.14.11.6330
9180.14.11.64/2780.14.11.65 to 80.14.11.9480.14.11.9530
9280.14.11.96/2780.14.11.97 to 80.14.11.12680.14.11.12730
9380.14.11.128/2780.14.11.129 to 80.14.11.15880.14.11.15930
9480.14.11.160/2780.14.11.161 to 80.14.11.19080.14.11.19130
9580.14.11.192/2780.14.11.193 to 80.14.11.22280.14.11.22330
9680.14.11.224/2780.14.11.225 to 80.14.11.25480.14.11.25530
9780.14.12.0/2780.14.12.1 to 80.14.12.3080.14.12.3130
9880.14.12.32/2780.14.12.33 to 80.14.12.6280.14.12.6330
9980.14.12.64/2780.14.12.65 to 80.14.12.9480.14.12.9530
10080.14.12.96/2780.14.12.97 to 80.14.12.12680.14.12.12730
10180.14.12.128/2780.14.12.129 to 80.14.12.15880.14.12.15930
10280.14.12.160/2780.14.12.161 to 80.14.12.19080.14.12.19130
10380.14.12.192/2780.14.12.193 to 80.14.12.22280.14.12.22330
10480.14.12.224/2780.14.12.225 to 80.14.12.25480.14.12.25530
10580.14.13.0/2780.14.13.1 to 80.14.13.3080.14.13.3130
10680.14.13.32/2780.14.13.33 to 80.14.13.6280.14.13.6330
10780.14.13.64/2780.14.13.65 to 80.14.13.9480.14.13.9530
10880.14.13.96/2780.14.13.97 to 80.14.13.12680.14.13.12730
10980.14.13.128/2780.14.13.129 to 80.14.13.15880.14.13.15930
11080.14.13.160/2780.14.13.161 to 80.14.13.19080.14.13.19130
11180.14.13.192/2780.14.13.193 to 80.14.13.22280.14.13.22330
11280.14.13.224/2780.14.13.225 to 80.14.13.25480.14.13.25530
11380.14.14.0/2780.14.14.1 to 80.14.14.3080.14.14.3130
11480.14.14.32/2780.14.14.33 to 80.14.14.6280.14.14.6330
11580.14.14.64/2780.14.14.65 to 80.14.14.9480.14.14.9530
11680.14.14.96/2780.14.14.97 to 80.14.14.12680.14.14.12730
11780.14.14.128/2780.14.14.129 to 80.14.14.15880.14.14.15930
11880.14.14.160/2780.14.14.161 to 80.14.14.19080.14.14.19130
11980.14.14.192/2780.14.14.193 to 80.14.14.22280.14.14.22330
12080.14.14.224/2780.14.14.225 to 80.14.14.25480.14.14.25530
12180.14.15.0/2780.14.15.1 to 80.14.15.3080.14.15.3130
12280.14.15.32/2780.14.15.33 to 80.14.15.6280.14.15.6330
12380.14.15.64/2780.14.15.65 to 80.14.15.9480.14.15.9530
12480.14.15.96/2780.14.15.97 to 80.14.15.12680.14.15.12730
12580.14.15.128/2780.14.15.129 to 80.14.15.15880.14.15.15930
12680.14.15.160/2780.14.15.161 to 80.14.15.19080.14.15.19130
12780.14.15.192/2780.14.15.193 to 80.14.15.22280.14.15.22330
12880.14.15.224/2780.14.15.225 to 80.14.15.25480.14.15.25530
12980.14.16.0/2780.14.16.1 to 80.14.16.3080.14.16.3130
13080.14.16.32/2780.14.16.33 to 80.14.16.6280.14.16.6330
13180.14.16.64/2780.14.16.65 to 80.14.16.9480.14.16.9530
13280.14.16.96/2780.14.16.97 to 80.14.16.12680.14.16.12730
13380.14.16.128/2780.14.16.129 to 80.14.16.15880.14.16.15930
13480.14.16.160/2780.14.16.161 to 80.14.16.19080.14.16.19130
13580.14.16.192/2780.14.16.193 to 80.14.16.22280.14.16.22330
13680.14.16.224/2780.14.16.225 to 80.14.16.25480.14.16.25530
13780.14.17.0/2780.14.17.1 to 80.14.17.3080.14.17.3130
13880.14.17.32/2780.14.17.33 to 80.14.17.6280.14.17.6330
13980.14.17.64/2780.14.17.65 to 80.14.17.9480.14.17.9530
14080.14.17.96/2780.14.17.97 to 80.14.17.12680.14.17.12730
14180.14.17.128/2780.14.17.129 to 80.14.17.15880.14.17.15930
14280.14.17.160/2780.14.17.161 to 80.14.17.19080.14.17.19130
14380.14.17.192/2780.14.17.193 to 80.14.17.22280.14.17.22330
14480.14.17.224/2780.14.17.225 to 80.14.17.25480.14.17.25530
14580.14.18.0/2780.14.18.1 to 80.14.18.3080.14.18.3130
14680.14.18.32/2780.14.18.33 to 80.14.18.6280.14.18.6330
14780.14.18.64/2780.14.18.65 to 80.14.18.9480.14.18.9530
14880.14.18.96/2780.14.18.97 to 80.14.18.12680.14.18.12730
14980.14.18.128/2780.14.18.129 to 80.14.18.15880.14.18.15930
15080.14.18.160/2780.14.18.161 to 80.14.18.19080.14.18.19130
15180.14.18.192/2780.14.18.193 to 80.14.18.22280.14.18.22330
15280.14.18.224/2780.14.18.225 to 80.14.18.25480.14.18.25530
15380.14.19.0/2780.14.19.1 to 80.14.19.3080.14.19.3130
15480.14.19.32/2780.14.19.33 to 80.14.19.6280.14.19.6330
15580.14.19.64/2780.14.19.65 to 80.14.19.9480.14.19.9530
15680.14.19.96/2780.14.19.97 to 80.14.19.12680.14.19.12730
15780.14.19.128/2780.14.19.129 to 80.14.19.15880.14.19.15930
15880.14.19.160/2780.14.19.161 to 80.14.19.19080.14.19.19130
15980.14.19.192/2780.14.19.193 to 80.14.19.22280.14.19.22330
16080.14.19.224/2780.14.19.225 to 80.14.19.25480.14.19.25530
16180.14.20.0/2780.14.20.1 to 80.14.20.3080.14.20.3130
16280.14.20.32/2780.14.20.33 to 80.14.20.6280.14.20.6330
16380.14.20.64/2780.14.20.65 to 80.14.20.9480.14.20.9530
16480.14.20.96/2780.14.20.97 to 80.14.20.12680.14.20.12730
16580.14.20.128/2780.14.20.129 to 80.14.20.15880.14.20.15930
16680.14.20.160/2780.14.20.161 to 80.14.20.19080.14.20.19130
16780.14.20.192/2780.14.20.193 to 80.14.20.22280.14.20.22330
16880.14.20.224/2780.14.20.225 to 80.14.20.25480.14.20.25530
16980.14.21.0/2780.14.21.1 to 80.14.21.3080.14.21.3130
17080.14.21.32/2780.14.21.33 to 80.14.21.6280.14.21.6330
17180.14.21.64/2780.14.21.65 to 80.14.21.9480.14.21.9530
17280.14.21.96/2780.14.21.97 to 80.14.21.12680.14.21.12730
17380.14.21.128/2780.14.21.129 to 80.14.21.15880.14.21.15930
17480.14.21.160/2780.14.21.161 to 80.14.21.19080.14.21.19130
17580.14.21.192/2780.14.21.193 to 80.14.21.22280.14.21.22330
17680.14.21.224/2780.14.21.225 to 80.14.21.25480.14.21.25530
17780.14.22.0/2780.14.22.1 to 80.14.22.3080.14.22.3130
17880.14.22.32/2780.14.22.33 to 80.14.22.6280.14.22.6330
17980.14.22.64/2780.14.22.65 to 80.14.22.9480.14.22.9530
18080.14.22.96/2780.14.22.97 to 80.14.22.12680.14.22.12730
18180.14.22.128/2780.14.22.129 to 80.14.22.15880.14.22.15930
18280.14.22.160/2780.14.22.161 to 80.14.22.19080.14.22.19130
18380.14.22.192/2780.14.22.193 to 80.14.22.22280.14.22.22330
18480.14.22.224/2780.14.22.225 to 80.14.22.25480.14.22.25530
18580.14.23.0/2780.14.23.1 to 80.14.23.3080.14.23.3130
18680.14.23.32/2780.14.23.33 to 80.14.23.6280.14.23.6330
18780.14.23.64/2780.14.23.65 to 80.14.23.9480.14.23.9530
18880.14.23.96/2780.14.23.97 to 80.14.23.12680.14.23.12730
18980.14.23.128/2780.14.23.129 to 80.14.23.15880.14.23.15930
19080.14.23.160/2780.14.23.161 to 80.14.23.19080.14.23.19130
19180.14.23.192/2780.14.23.193 to 80.14.23.22280.14.23.22330
19280.14.23.224/2780.14.23.225 to 80.14.23.25480.14.23.25530
19380.14.24.0/2780.14.24.1 to 80.14.24.3080.14.24.3130
19480.14.24.32/2780.14.24.33 to 80.14.24.6280.14.24.6330
19580.14.24.64/2780.14.24.65 to 80.14.24.9480.14.24.9530
19680.14.24.96/2780.14.24.97 to 80.14.24.12680.14.24.12730
19780.14.24.128/2780.14.24.129 to 80.14.24.15880.14.24.15930
19880.14.24.160/2780.14.24.161 to 80.14.24.19080.14.24.19130
19980.14.24.192/2780.14.24.193 to 80.14.24.22280.14.24.22330
20080.14.24.224/2780.14.24.225 to 80.14.24.25480.14.24.25530
20180.14.25.0/2780.14.25.1 to 80.14.25.3080.14.25.3130
20280.14.25.32/2780.14.25.33 to 80.14.25.6280.14.25.6330
20380.14.25.64/2780.14.25.65 to 80.14.25.9480.14.25.9530
20480.14.25.96/2780.14.25.97 to 80.14.25.12680.14.25.12730
20580.14.25.128/2780.14.25.129 to 80.14.25.15880.14.25.15930
20680.14.25.160/2780.14.25.161 to 80.14.25.19080.14.25.19130
20780.14.25.192/2780.14.25.193 to 80.14.25.22280.14.25.22330
20880.14.25.224/2780.14.25.225 to 80.14.25.25480.14.25.25530
20980.14.26.0/2780.14.26.1 to 80.14.26.3080.14.26.3130
21080.14.26.32/2780.14.26.33 to 80.14.26.6280.14.26.6330
21180.14.26.64/2780.14.26.65 to 80.14.26.9480.14.26.9530
21280.14.26.96/2780.14.26.97 to 80.14.26.12680.14.26.12730
21380.14.26.128/2780.14.26.129 to 80.14.26.15880.14.26.15930
21480.14.26.160/2780.14.26.161 to 80.14.26.19080.14.26.19130
21580.14.26.192/2780.14.26.193 to 80.14.26.22280.14.26.22330
21680.14.26.224/2780.14.26.225 to 80.14.26.25480.14.26.25530
21780.14.27.0/2780.14.27.1 to 80.14.27.3080.14.27.3130
21880.14.27.32/2780.14.27.33 to 80.14.27.6280.14.27.6330
21980.14.27.64/2780.14.27.65 to 80.14.27.9480.14.27.9530
22080.14.27.96/2780.14.27.97 to 80.14.27.12680.14.27.12730
22180.14.27.128/2780.14.27.129 to 80.14.27.15880.14.27.15930
22280.14.27.160/2780.14.27.161 to 80.14.27.19080.14.27.19130
22380.14.27.192/2780.14.27.193 to 80.14.27.22280.14.27.22330
22480.14.27.224/2780.14.27.225 to 80.14.27.25480.14.27.25530
22580.14.28.0/2780.14.28.1 to 80.14.28.3080.14.28.3130
22680.14.28.32/2780.14.28.33 to 80.14.28.6280.14.28.6330
22780.14.28.64/2780.14.28.65 to 80.14.28.9480.14.28.9530
22880.14.28.96/2780.14.28.97 to 80.14.28.12680.14.28.12730
22980.14.28.128/2780.14.28.129 to 80.14.28.15880.14.28.15930
23080.14.28.160/2780.14.28.161 to 80.14.28.19080.14.28.19130
23180.14.28.192/2780.14.28.193 to 80.14.28.22280.14.28.22330
23280.14.28.224/2780.14.28.225 to 80.14.28.25480.14.28.25530
23380.14.29.0/2780.14.29.1 to 80.14.29.3080.14.29.3130
23480.14.29.32/2780.14.29.33 to 80.14.29.6280.14.29.6330
23580.14.29.64/2780.14.29.65 to 80.14.29.9480.14.29.9530
23680.14.29.96/2780.14.29.97 to 80.14.29.12680.14.29.12730
23780.14.29.128/2780.14.29.129 to 80.14.29.15880.14.29.15930
23880.14.29.160/2780.14.29.161 to 80.14.29.19080.14.29.19130
23980.14.29.192/2780.14.29.193 to 80.14.29.22280.14.29.22330
24080.14.29.224/2780.14.29.225 to 80.14.29.25480.14.29.25530
24180.14.30.0/2780.14.30.1 to 80.14.30.3080.14.30.3130
24280.14.30.32/2780.14.30.33 to 80.14.30.6280.14.30.6330
24380.14.30.64/2780.14.30.65 to 80.14.30.9480.14.30.9530
24480.14.30.96/2780.14.30.97 to 80.14.30.12680.14.30.12730
24580.14.30.128/2780.14.30.129 to 80.14.30.15880.14.30.15930
24680.14.30.160/2780.14.30.161 to 80.14.30.19080.14.30.19130
24780.14.30.192/2780.14.30.193 to 80.14.30.22280.14.30.22330
24880.14.30.224/2780.14.30.225 to 80.14.30.25480.14.30.25530
24980.14.31.0/2780.14.31.1 to 80.14.31.3080.14.31.3130
25080.14.31.32/2780.14.31.33 to 80.14.31.6280.14.31.6330
25180.14.31.64/2780.14.31.65 to 80.14.31.9480.14.31.9530
25280.14.31.96/2780.14.31.97 to 80.14.31.12680.14.31.12730
25380.14.31.128/2780.14.31.129 to 80.14.31.15880.14.31.15930
25480.14.31.160/2780.14.31.161 to 80.14.31.19080.14.31.19130
25580.14.31.192/2780.14.31.193 to 80.14.31.22280.14.31.22330
25680.14.31.224/2780.14.31.225 to 80.14.31.25480.14.31.25530

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.