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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.

Network98.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
98.0.0.0
Broadcast address
98.255.255.255
First usable
98.0.0.1
Last usable
98.255.255.254
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 62000000 · Integer 1644167168 to 1660944383
Reverse DNS zone
98.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100010..00000000.00000000.0000000098.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01100010..00000000.00000000.0000000098.0.0.0
Broadcast01100010..11111111.11111111.1111111198.255.255.255
Split into smaller subnets/20
/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)

98.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
198.0.0.0/2098.0.0.1 to 98.0.15.25498.0.15.2554,094
298.0.16.0/2098.0.16.1 to 98.0.31.25498.0.31.2554,094
398.0.32.0/2098.0.32.1 to 98.0.47.25498.0.47.2554,094
498.0.48.0/2098.0.48.1 to 98.0.63.25498.0.63.2554,094
598.0.64.0/2098.0.64.1 to 98.0.79.25498.0.79.2554,094
698.0.80.0/2098.0.80.1 to 98.0.95.25498.0.95.2554,094
798.0.96.0/2098.0.96.1 to 98.0.111.25498.0.111.2554,094
898.0.112.0/2098.0.112.1 to 98.0.127.25498.0.127.2554,094
998.0.128.0/2098.0.128.1 to 98.0.143.25498.0.143.2554,094
1098.0.144.0/2098.0.144.1 to 98.0.159.25498.0.159.2554,094
1198.0.160.0/2098.0.160.1 to 98.0.175.25498.0.175.2554,094
1298.0.176.0/2098.0.176.1 to 98.0.191.25498.0.191.2554,094
1398.0.192.0/2098.0.192.1 to 98.0.207.25498.0.207.2554,094
1498.0.208.0/2098.0.208.1 to 98.0.223.25498.0.223.2554,094
1598.0.224.0/2098.0.224.1 to 98.0.239.25498.0.239.2554,094
1698.0.240.0/2098.0.240.1 to 98.0.255.25498.0.255.2554,094
1798.1.0.0/2098.1.0.1 to 98.1.15.25498.1.15.2554,094
1898.1.16.0/2098.1.16.1 to 98.1.31.25498.1.31.2554,094
1998.1.32.0/2098.1.32.1 to 98.1.47.25498.1.47.2554,094
2098.1.48.0/2098.1.48.1 to 98.1.63.25498.1.63.2554,094
2198.1.64.0/2098.1.64.1 to 98.1.79.25498.1.79.2554,094
2298.1.80.0/2098.1.80.1 to 98.1.95.25498.1.95.2554,094
2398.1.96.0/2098.1.96.1 to 98.1.111.25498.1.111.2554,094
2498.1.112.0/2098.1.112.1 to 98.1.127.25498.1.127.2554,094
2598.1.128.0/2098.1.128.1 to 98.1.143.25498.1.143.2554,094
2698.1.144.0/2098.1.144.1 to 98.1.159.25498.1.159.2554,094
2798.1.160.0/2098.1.160.1 to 98.1.175.25498.1.175.2554,094
2898.1.176.0/2098.1.176.1 to 98.1.191.25498.1.191.2554,094
2998.1.192.0/2098.1.192.1 to 98.1.207.25498.1.207.2554,094
3098.1.208.0/2098.1.208.1 to 98.1.223.25498.1.223.2554,094
3198.1.224.0/2098.1.224.1 to 98.1.239.25498.1.239.2554,094
3298.1.240.0/2098.1.240.1 to 98.1.255.25498.1.255.2554,094
3398.2.0.0/2098.2.0.1 to 98.2.15.25498.2.15.2554,094
3498.2.16.0/2098.2.16.1 to 98.2.31.25498.2.31.2554,094
3598.2.32.0/2098.2.32.1 to 98.2.47.25498.2.47.2554,094
3698.2.48.0/2098.2.48.1 to 98.2.63.25498.2.63.2554,094
3798.2.64.0/2098.2.64.1 to 98.2.79.25498.2.79.2554,094
3898.2.80.0/2098.2.80.1 to 98.2.95.25498.2.95.2554,094
3998.2.96.0/2098.2.96.1 to 98.2.111.25498.2.111.2554,094
4098.2.112.0/2098.2.112.1 to 98.2.127.25498.2.127.2554,094
4198.2.128.0/2098.2.128.1 to 98.2.143.25498.2.143.2554,094
4298.2.144.0/2098.2.144.1 to 98.2.159.25498.2.159.2554,094
4398.2.160.0/2098.2.160.1 to 98.2.175.25498.2.175.2554,094
4498.2.176.0/2098.2.176.1 to 98.2.191.25498.2.191.2554,094
4598.2.192.0/2098.2.192.1 to 98.2.207.25498.2.207.2554,094
4698.2.208.0/2098.2.208.1 to 98.2.223.25498.2.223.2554,094
4798.2.224.0/2098.2.224.1 to 98.2.239.25498.2.239.2554,094
4898.2.240.0/2098.2.240.1 to 98.2.255.25498.2.255.2554,094
4998.3.0.0/2098.3.0.1 to 98.3.15.25498.3.15.2554,094
5098.3.16.0/2098.3.16.1 to 98.3.31.25498.3.31.2554,094
5198.3.32.0/2098.3.32.1 to 98.3.47.25498.3.47.2554,094
5298.3.48.0/2098.3.48.1 to 98.3.63.25498.3.63.2554,094
5398.3.64.0/2098.3.64.1 to 98.3.79.25498.3.79.2554,094
5498.3.80.0/2098.3.80.1 to 98.3.95.25498.3.95.2554,094
5598.3.96.0/2098.3.96.1 to 98.3.111.25498.3.111.2554,094
5698.3.112.0/2098.3.112.1 to 98.3.127.25498.3.127.2554,094
5798.3.128.0/2098.3.128.1 to 98.3.143.25498.3.143.2554,094
5898.3.144.0/2098.3.144.1 to 98.3.159.25498.3.159.2554,094
5998.3.160.0/2098.3.160.1 to 98.3.175.25498.3.175.2554,094
6098.3.176.0/2098.3.176.1 to 98.3.191.25498.3.191.2554,094
6198.3.192.0/2098.3.192.1 to 98.3.207.25498.3.207.2554,094
6298.3.208.0/2098.3.208.1 to 98.3.223.25498.3.223.2554,094
6398.3.224.0/2098.3.224.1 to 98.3.239.25498.3.239.2554,094
6498.3.240.0/2098.3.240.1 to 98.3.255.25498.3.255.2554,094
6598.4.0.0/2098.4.0.1 to 98.4.15.25498.4.15.2554,094
6698.4.16.0/2098.4.16.1 to 98.4.31.25498.4.31.2554,094
6798.4.32.0/2098.4.32.1 to 98.4.47.25498.4.47.2554,094
6898.4.48.0/2098.4.48.1 to 98.4.63.25498.4.63.2554,094
6998.4.64.0/2098.4.64.1 to 98.4.79.25498.4.79.2554,094
7098.4.80.0/2098.4.80.1 to 98.4.95.25498.4.95.2554,094
7198.4.96.0/2098.4.96.1 to 98.4.111.25498.4.111.2554,094
7298.4.112.0/2098.4.112.1 to 98.4.127.25498.4.127.2554,094
7398.4.128.0/2098.4.128.1 to 98.4.143.25498.4.143.2554,094
7498.4.144.0/2098.4.144.1 to 98.4.159.25498.4.159.2554,094
7598.4.160.0/2098.4.160.1 to 98.4.175.25498.4.175.2554,094
7698.4.176.0/2098.4.176.1 to 98.4.191.25498.4.191.2554,094
7798.4.192.0/2098.4.192.1 to 98.4.207.25498.4.207.2554,094
7898.4.208.0/2098.4.208.1 to 98.4.223.25498.4.223.2554,094
7998.4.224.0/2098.4.224.1 to 98.4.239.25498.4.239.2554,094
8098.4.240.0/2098.4.240.1 to 98.4.255.25498.4.255.2554,094
8198.5.0.0/2098.5.0.1 to 98.5.15.25498.5.15.2554,094
8298.5.16.0/2098.5.16.1 to 98.5.31.25498.5.31.2554,094
8398.5.32.0/2098.5.32.1 to 98.5.47.25498.5.47.2554,094
8498.5.48.0/2098.5.48.1 to 98.5.63.25498.5.63.2554,094
8598.5.64.0/2098.5.64.1 to 98.5.79.25498.5.79.2554,094
8698.5.80.0/2098.5.80.1 to 98.5.95.25498.5.95.2554,094
8798.5.96.0/2098.5.96.1 to 98.5.111.25498.5.111.2554,094
8898.5.112.0/2098.5.112.1 to 98.5.127.25498.5.127.2554,094
8998.5.128.0/2098.5.128.1 to 98.5.143.25498.5.143.2554,094
9098.5.144.0/2098.5.144.1 to 98.5.159.25498.5.159.2554,094
9198.5.160.0/2098.5.160.1 to 98.5.175.25498.5.175.2554,094
9298.5.176.0/2098.5.176.1 to 98.5.191.25498.5.191.2554,094
9398.5.192.0/2098.5.192.1 to 98.5.207.25498.5.207.2554,094
9498.5.208.0/2098.5.208.1 to 98.5.223.25498.5.223.2554,094
9598.5.224.0/2098.5.224.1 to 98.5.239.25498.5.239.2554,094
9698.5.240.0/2098.5.240.1 to 98.5.255.25498.5.255.2554,094
9798.6.0.0/2098.6.0.1 to 98.6.15.25498.6.15.2554,094
9898.6.16.0/2098.6.16.1 to 98.6.31.25498.6.31.2554,094
9998.6.32.0/2098.6.32.1 to 98.6.47.25498.6.47.2554,094
10098.6.48.0/2098.6.48.1 to 98.6.63.25498.6.63.2554,094
10198.6.64.0/2098.6.64.1 to 98.6.79.25498.6.79.2554,094
10298.6.80.0/2098.6.80.1 to 98.6.95.25498.6.95.2554,094
10398.6.96.0/2098.6.96.1 to 98.6.111.25498.6.111.2554,094
10498.6.112.0/2098.6.112.1 to 98.6.127.25498.6.127.2554,094
10598.6.128.0/2098.6.128.1 to 98.6.143.25498.6.143.2554,094
10698.6.144.0/2098.6.144.1 to 98.6.159.25498.6.159.2554,094
10798.6.160.0/2098.6.160.1 to 98.6.175.25498.6.175.2554,094
10898.6.176.0/2098.6.176.1 to 98.6.191.25498.6.191.2554,094
10998.6.192.0/2098.6.192.1 to 98.6.207.25498.6.207.2554,094
11098.6.208.0/2098.6.208.1 to 98.6.223.25498.6.223.2554,094
11198.6.224.0/2098.6.224.1 to 98.6.239.25498.6.239.2554,094
11298.6.240.0/2098.6.240.1 to 98.6.255.25498.6.255.2554,094
11398.7.0.0/2098.7.0.1 to 98.7.15.25498.7.15.2554,094
11498.7.16.0/2098.7.16.1 to 98.7.31.25498.7.31.2554,094
11598.7.32.0/2098.7.32.1 to 98.7.47.25498.7.47.2554,094
11698.7.48.0/2098.7.48.1 to 98.7.63.25498.7.63.2554,094
11798.7.64.0/2098.7.64.1 to 98.7.79.25498.7.79.2554,094
11898.7.80.0/2098.7.80.1 to 98.7.95.25498.7.95.2554,094
11998.7.96.0/2098.7.96.1 to 98.7.111.25498.7.111.2554,094
12098.7.112.0/2098.7.112.1 to 98.7.127.25498.7.127.2554,094
12198.7.128.0/2098.7.128.1 to 98.7.143.25498.7.143.2554,094
12298.7.144.0/2098.7.144.1 to 98.7.159.25498.7.159.2554,094
12398.7.160.0/2098.7.160.1 to 98.7.175.25498.7.175.2554,094
12498.7.176.0/2098.7.176.1 to 98.7.191.25498.7.191.2554,094
12598.7.192.0/2098.7.192.1 to 98.7.207.25498.7.207.2554,094
12698.7.208.0/2098.7.208.1 to 98.7.223.25498.7.223.2554,094
12798.7.224.0/2098.7.224.1 to 98.7.239.25498.7.239.2554,094
12898.7.240.0/2098.7.240.1 to 98.7.255.25498.7.255.2554,094
12998.8.0.0/2098.8.0.1 to 98.8.15.25498.8.15.2554,094
13098.8.16.0/2098.8.16.1 to 98.8.31.25498.8.31.2554,094
13198.8.32.0/2098.8.32.1 to 98.8.47.25498.8.47.2554,094
13298.8.48.0/2098.8.48.1 to 98.8.63.25498.8.63.2554,094
13398.8.64.0/2098.8.64.1 to 98.8.79.25498.8.79.2554,094
13498.8.80.0/2098.8.80.1 to 98.8.95.25498.8.95.2554,094
13598.8.96.0/2098.8.96.1 to 98.8.111.25498.8.111.2554,094
13698.8.112.0/2098.8.112.1 to 98.8.127.25498.8.127.2554,094
13798.8.128.0/2098.8.128.1 to 98.8.143.25498.8.143.2554,094
13898.8.144.0/2098.8.144.1 to 98.8.159.25498.8.159.2554,094
13998.8.160.0/2098.8.160.1 to 98.8.175.25498.8.175.2554,094
14098.8.176.0/2098.8.176.1 to 98.8.191.25498.8.191.2554,094
14198.8.192.0/2098.8.192.1 to 98.8.207.25498.8.207.2554,094
14298.8.208.0/2098.8.208.1 to 98.8.223.25498.8.223.2554,094
14398.8.224.0/2098.8.224.1 to 98.8.239.25498.8.239.2554,094
14498.8.240.0/2098.8.240.1 to 98.8.255.25498.8.255.2554,094
14598.9.0.0/2098.9.0.1 to 98.9.15.25498.9.15.2554,094
14698.9.16.0/2098.9.16.1 to 98.9.31.25498.9.31.2554,094
14798.9.32.0/2098.9.32.1 to 98.9.47.25498.9.47.2554,094
14898.9.48.0/2098.9.48.1 to 98.9.63.25498.9.63.2554,094
14998.9.64.0/2098.9.64.1 to 98.9.79.25498.9.79.2554,094
15098.9.80.0/2098.9.80.1 to 98.9.95.25498.9.95.2554,094
15198.9.96.0/2098.9.96.1 to 98.9.111.25498.9.111.2554,094
15298.9.112.0/2098.9.112.1 to 98.9.127.25498.9.127.2554,094
15398.9.128.0/2098.9.128.1 to 98.9.143.25498.9.143.2554,094
15498.9.144.0/2098.9.144.1 to 98.9.159.25498.9.159.2554,094
15598.9.160.0/2098.9.160.1 to 98.9.175.25498.9.175.2554,094
15698.9.176.0/2098.9.176.1 to 98.9.191.25498.9.191.2554,094
15798.9.192.0/2098.9.192.1 to 98.9.207.25498.9.207.2554,094
15898.9.208.0/2098.9.208.1 to 98.9.223.25498.9.223.2554,094
15998.9.224.0/2098.9.224.1 to 98.9.239.25498.9.239.2554,094
16098.9.240.0/2098.9.240.1 to 98.9.255.25498.9.255.2554,094
16198.10.0.0/2098.10.0.1 to 98.10.15.25498.10.15.2554,094
16298.10.16.0/2098.10.16.1 to 98.10.31.25498.10.31.2554,094
16398.10.32.0/2098.10.32.1 to 98.10.47.25498.10.47.2554,094
16498.10.48.0/2098.10.48.1 to 98.10.63.25498.10.63.2554,094
16598.10.64.0/2098.10.64.1 to 98.10.79.25498.10.79.2554,094
16698.10.80.0/2098.10.80.1 to 98.10.95.25498.10.95.2554,094
16798.10.96.0/2098.10.96.1 to 98.10.111.25498.10.111.2554,094
16898.10.112.0/2098.10.112.1 to 98.10.127.25498.10.127.2554,094
16998.10.128.0/2098.10.128.1 to 98.10.143.25498.10.143.2554,094
17098.10.144.0/2098.10.144.1 to 98.10.159.25498.10.159.2554,094
17198.10.160.0/2098.10.160.1 to 98.10.175.25498.10.175.2554,094
17298.10.176.0/2098.10.176.1 to 98.10.191.25498.10.191.2554,094
17398.10.192.0/2098.10.192.1 to 98.10.207.25498.10.207.2554,094
17498.10.208.0/2098.10.208.1 to 98.10.223.25498.10.223.2554,094
17598.10.224.0/2098.10.224.1 to 98.10.239.25498.10.239.2554,094
17698.10.240.0/2098.10.240.1 to 98.10.255.25498.10.255.2554,094
17798.11.0.0/2098.11.0.1 to 98.11.15.25498.11.15.2554,094
17898.11.16.0/2098.11.16.1 to 98.11.31.25498.11.31.2554,094
17998.11.32.0/2098.11.32.1 to 98.11.47.25498.11.47.2554,094
18098.11.48.0/2098.11.48.1 to 98.11.63.25498.11.63.2554,094
18198.11.64.0/2098.11.64.1 to 98.11.79.25498.11.79.2554,094
18298.11.80.0/2098.11.80.1 to 98.11.95.25498.11.95.2554,094
18398.11.96.0/2098.11.96.1 to 98.11.111.25498.11.111.2554,094
18498.11.112.0/2098.11.112.1 to 98.11.127.25498.11.127.2554,094
18598.11.128.0/2098.11.128.1 to 98.11.143.25498.11.143.2554,094
18698.11.144.0/2098.11.144.1 to 98.11.159.25498.11.159.2554,094
18798.11.160.0/2098.11.160.1 to 98.11.175.25498.11.175.2554,094
18898.11.176.0/2098.11.176.1 to 98.11.191.25498.11.191.2554,094
18998.11.192.0/2098.11.192.1 to 98.11.207.25498.11.207.2554,094
19098.11.208.0/2098.11.208.1 to 98.11.223.25498.11.223.2554,094
19198.11.224.0/2098.11.224.1 to 98.11.239.25498.11.239.2554,094
19298.11.240.0/2098.11.240.1 to 98.11.255.25498.11.255.2554,094
19398.12.0.0/2098.12.0.1 to 98.12.15.25498.12.15.2554,094
19498.12.16.0/2098.12.16.1 to 98.12.31.25498.12.31.2554,094
19598.12.32.0/2098.12.32.1 to 98.12.47.25498.12.47.2554,094
19698.12.48.0/2098.12.48.1 to 98.12.63.25498.12.63.2554,094
19798.12.64.0/2098.12.64.1 to 98.12.79.25498.12.79.2554,094
19898.12.80.0/2098.12.80.1 to 98.12.95.25498.12.95.2554,094
19998.12.96.0/2098.12.96.1 to 98.12.111.25498.12.111.2554,094
20098.12.112.0/2098.12.112.1 to 98.12.127.25498.12.127.2554,094
20198.12.128.0/2098.12.128.1 to 98.12.143.25498.12.143.2554,094
20298.12.144.0/2098.12.144.1 to 98.12.159.25498.12.159.2554,094
20398.12.160.0/2098.12.160.1 to 98.12.175.25498.12.175.2554,094
20498.12.176.0/2098.12.176.1 to 98.12.191.25498.12.191.2554,094
20598.12.192.0/2098.12.192.1 to 98.12.207.25498.12.207.2554,094
20698.12.208.0/2098.12.208.1 to 98.12.223.25498.12.223.2554,094
20798.12.224.0/2098.12.224.1 to 98.12.239.25498.12.239.2554,094
20898.12.240.0/2098.12.240.1 to 98.12.255.25498.12.255.2554,094
20998.13.0.0/2098.13.0.1 to 98.13.15.25498.13.15.2554,094
21098.13.16.0/2098.13.16.1 to 98.13.31.25498.13.31.2554,094
21198.13.32.0/2098.13.32.1 to 98.13.47.25498.13.47.2554,094
21298.13.48.0/2098.13.48.1 to 98.13.63.25498.13.63.2554,094
21398.13.64.0/2098.13.64.1 to 98.13.79.25498.13.79.2554,094
21498.13.80.0/2098.13.80.1 to 98.13.95.25498.13.95.2554,094
21598.13.96.0/2098.13.96.1 to 98.13.111.25498.13.111.2554,094
21698.13.112.0/2098.13.112.1 to 98.13.127.25498.13.127.2554,094
21798.13.128.0/2098.13.128.1 to 98.13.143.25498.13.143.2554,094
21898.13.144.0/2098.13.144.1 to 98.13.159.25498.13.159.2554,094
21998.13.160.0/2098.13.160.1 to 98.13.175.25498.13.175.2554,094
22098.13.176.0/2098.13.176.1 to 98.13.191.25498.13.191.2554,094
22198.13.192.0/2098.13.192.1 to 98.13.207.25498.13.207.2554,094
22298.13.208.0/2098.13.208.1 to 98.13.223.25498.13.223.2554,094
22398.13.224.0/2098.13.224.1 to 98.13.239.25498.13.239.2554,094
22498.13.240.0/2098.13.240.1 to 98.13.255.25498.13.255.2554,094
22598.14.0.0/2098.14.0.1 to 98.14.15.25498.14.15.2554,094
22698.14.16.0/2098.14.16.1 to 98.14.31.25498.14.31.2554,094
22798.14.32.0/2098.14.32.1 to 98.14.47.25498.14.47.2554,094
22898.14.48.0/2098.14.48.1 to 98.14.63.25498.14.63.2554,094
22998.14.64.0/2098.14.64.1 to 98.14.79.25498.14.79.2554,094
23098.14.80.0/2098.14.80.1 to 98.14.95.25498.14.95.2554,094
23198.14.96.0/2098.14.96.1 to 98.14.111.25498.14.111.2554,094
23298.14.112.0/2098.14.112.1 to 98.14.127.25498.14.127.2554,094
23398.14.128.0/2098.14.128.1 to 98.14.143.25498.14.143.2554,094
23498.14.144.0/2098.14.144.1 to 98.14.159.25498.14.159.2554,094
23598.14.160.0/2098.14.160.1 to 98.14.175.25498.14.175.2554,094
23698.14.176.0/2098.14.176.1 to 98.14.191.25498.14.191.2554,094
23798.14.192.0/2098.14.192.1 to 98.14.207.25498.14.207.2554,094
23898.14.208.0/2098.14.208.1 to 98.14.223.25498.14.223.2554,094
23998.14.224.0/2098.14.224.1 to 98.14.239.25498.14.239.2554,094
24098.14.240.0/2098.14.240.1 to 98.14.255.25498.14.255.2554,094
24198.15.0.0/2098.15.0.1 to 98.15.15.25498.15.15.2554,094
24298.15.16.0/2098.15.16.1 to 98.15.31.25498.15.31.2554,094
24398.15.32.0/2098.15.32.1 to 98.15.47.25498.15.47.2554,094
24498.15.48.0/2098.15.48.1 to 98.15.63.25498.15.63.2554,094
24598.15.64.0/2098.15.64.1 to 98.15.79.25498.15.79.2554,094
24698.15.80.0/2098.15.80.1 to 98.15.95.25498.15.95.2554,094
24798.15.96.0/2098.15.96.1 to 98.15.111.25498.15.111.2554,094
24898.15.112.0/2098.15.112.1 to 98.15.127.25498.15.127.2554,094
24998.15.128.0/2098.15.128.1 to 98.15.143.25498.15.143.2554,094
25098.15.144.0/2098.15.144.1 to 98.15.159.25498.15.159.2554,094
25198.15.160.0/2098.15.160.1 to 98.15.175.25498.15.175.2554,094
25298.15.176.0/2098.15.176.1 to 98.15.191.25498.15.191.2554,094
25398.15.192.0/2098.15.192.1 to 98.15.207.25498.15.207.2554,094
25498.15.208.0/2098.15.208.1 to 98.15.223.25498.15.223.2554,094
25598.15.224.0/2098.15.224.1 to 98.15.239.25498.15.239.2554,094
25698.15.240.0/2098.15.240.1 to 98.15.255.25498.15.255.2554,094

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.