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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.

Network98.232.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
98.232.0.0
Broadcast address
98.239.255.255
First usable
98.232.0.1
Last usable
98.239.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 62E80000 · Integer 1659371520 to 1659895807
Reverse DNS zones
232.98.in-addr.arpa
233.98.in-addr.arpa
234.98.in-addr.arpa
235.98.in-addr.arpa
236.98.in-addr.arpa
237.98.in-addr.arpa
238.98.in-addr.arpa
239.98.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100010.11101000.00000000.0000000098.232.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01100010.11101000.00000000.0000000098.232.0.0
Broadcast01100010.11101111.11111111.1111111198.239.255.255
Split into smaller subnets/24
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

98.232.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
198.232.0.0/2498.232.0.1 to 98.232.0.25498.232.0.255254
298.232.1.0/2498.232.1.1 to 98.232.1.25498.232.1.255254
398.232.2.0/2498.232.2.1 to 98.232.2.25498.232.2.255254
498.232.3.0/2498.232.3.1 to 98.232.3.25498.232.3.255254
598.232.4.0/2498.232.4.1 to 98.232.4.25498.232.4.255254
698.232.5.0/2498.232.5.1 to 98.232.5.25498.232.5.255254
798.232.6.0/2498.232.6.1 to 98.232.6.25498.232.6.255254
898.232.7.0/2498.232.7.1 to 98.232.7.25498.232.7.255254
998.232.8.0/2498.232.8.1 to 98.232.8.25498.232.8.255254
1098.232.9.0/2498.232.9.1 to 98.232.9.25498.232.9.255254
1198.232.10.0/2498.232.10.1 to 98.232.10.25498.232.10.255254
1298.232.11.0/2498.232.11.1 to 98.232.11.25498.232.11.255254
1398.232.12.0/2498.232.12.1 to 98.232.12.25498.232.12.255254
1498.232.13.0/2498.232.13.1 to 98.232.13.25498.232.13.255254
1598.232.14.0/2498.232.14.1 to 98.232.14.25498.232.14.255254
1698.232.15.0/2498.232.15.1 to 98.232.15.25498.232.15.255254
1798.232.16.0/2498.232.16.1 to 98.232.16.25498.232.16.255254
1898.232.17.0/2498.232.17.1 to 98.232.17.25498.232.17.255254
1998.232.18.0/2498.232.18.1 to 98.232.18.25498.232.18.255254
2098.232.19.0/2498.232.19.1 to 98.232.19.25498.232.19.255254
2198.232.20.0/2498.232.20.1 to 98.232.20.25498.232.20.255254
2298.232.21.0/2498.232.21.1 to 98.232.21.25498.232.21.255254
2398.232.22.0/2498.232.22.1 to 98.232.22.25498.232.22.255254
2498.232.23.0/2498.232.23.1 to 98.232.23.25498.232.23.255254
2598.232.24.0/2498.232.24.1 to 98.232.24.25498.232.24.255254
2698.232.25.0/2498.232.25.1 to 98.232.25.25498.232.25.255254
2798.232.26.0/2498.232.26.1 to 98.232.26.25498.232.26.255254
2898.232.27.0/2498.232.27.1 to 98.232.27.25498.232.27.255254
2998.232.28.0/2498.232.28.1 to 98.232.28.25498.232.28.255254
3098.232.29.0/2498.232.29.1 to 98.232.29.25498.232.29.255254
3198.232.30.0/2498.232.30.1 to 98.232.30.25498.232.30.255254
3298.232.31.0/2498.232.31.1 to 98.232.31.25498.232.31.255254
3398.232.32.0/2498.232.32.1 to 98.232.32.25498.232.32.255254
3498.232.33.0/2498.232.33.1 to 98.232.33.25498.232.33.255254
3598.232.34.0/2498.232.34.1 to 98.232.34.25498.232.34.255254
3698.232.35.0/2498.232.35.1 to 98.232.35.25498.232.35.255254
3798.232.36.0/2498.232.36.1 to 98.232.36.25498.232.36.255254
3898.232.37.0/2498.232.37.1 to 98.232.37.25498.232.37.255254
3998.232.38.0/2498.232.38.1 to 98.232.38.25498.232.38.255254
4098.232.39.0/2498.232.39.1 to 98.232.39.25498.232.39.255254
4198.232.40.0/2498.232.40.1 to 98.232.40.25498.232.40.255254
4298.232.41.0/2498.232.41.1 to 98.232.41.25498.232.41.255254
4398.232.42.0/2498.232.42.1 to 98.232.42.25498.232.42.255254
4498.232.43.0/2498.232.43.1 to 98.232.43.25498.232.43.255254
4598.232.44.0/2498.232.44.1 to 98.232.44.25498.232.44.255254
4698.232.45.0/2498.232.45.1 to 98.232.45.25498.232.45.255254
4798.232.46.0/2498.232.46.1 to 98.232.46.25498.232.46.255254
4898.232.47.0/2498.232.47.1 to 98.232.47.25498.232.47.255254
4998.232.48.0/2498.232.48.1 to 98.232.48.25498.232.48.255254
5098.232.49.0/2498.232.49.1 to 98.232.49.25498.232.49.255254
5198.232.50.0/2498.232.50.1 to 98.232.50.25498.232.50.255254
5298.232.51.0/2498.232.51.1 to 98.232.51.25498.232.51.255254
5398.232.52.0/2498.232.52.1 to 98.232.52.25498.232.52.255254
5498.232.53.0/2498.232.53.1 to 98.232.53.25498.232.53.255254
5598.232.54.0/2498.232.54.1 to 98.232.54.25498.232.54.255254
5698.232.55.0/2498.232.55.1 to 98.232.55.25498.232.55.255254
5798.232.56.0/2498.232.56.1 to 98.232.56.25498.232.56.255254
5898.232.57.0/2498.232.57.1 to 98.232.57.25498.232.57.255254
5998.232.58.0/2498.232.58.1 to 98.232.58.25498.232.58.255254
6098.232.59.0/2498.232.59.1 to 98.232.59.25498.232.59.255254
6198.232.60.0/2498.232.60.1 to 98.232.60.25498.232.60.255254
6298.232.61.0/2498.232.61.1 to 98.232.61.25498.232.61.255254
6398.232.62.0/2498.232.62.1 to 98.232.62.25498.232.62.255254
6498.232.63.0/2498.232.63.1 to 98.232.63.25498.232.63.255254
6598.232.64.0/2498.232.64.1 to 98.232.64.25498.232.64.255254
6698.232.65.0/2498.232.65.1 to 98.232.65.25498.232.65.255254
6798.232.66.0/2498.232.66.1 to 98.232.66.25498.232.66.255254
6898.232.67.0/2498.232.67.1 to 98.232.67.25498.232.67.255254
6998.232.68.0/2498.232.68.1 to 98.232.68.25498.232.68.255254
7098.232.69.0/2498.232.69.1 to 98.232.69.25498.232.69.255254
7198.232.70.0/2498.232.70.1 to 98.232.70.25498.232.70.255254
7298.232.71.0/2498.232.71.1 to 98.232.71.25498.232.71.255254
7398.232.72.0/2498.232.72.1 to 98.232.72.25498.232.72.255254
7498.232.73.0/2498.232.73.1 to 98.232.73.25498.232.73.255254
7598.232.74.0/2498.232.74.1 to 98.232.74.25498.232.74.255254
7698.232.75.0/2498.232.75.1 to 98.232.75.25498.232.75.255254
7798.232.76.0/2498.232.76.1 to 98.232.76.25498.232.76.255254
7898.232.77.0/2498.232.77.1 to 98.232.77.25498.232.77.255254
7998.232.78.0/2498.232.78.1 to 98.232.78.25498.232.78.255254
8098.232.79.0/2498.232.79.1 to 98.232.79.25498.232.79.255254
8198.232.80.0/2498.232.80.1 to 98.232.80.25498.232.80.255254
8298.232.81.0/2498.232.81.1 to 98.232.81.25498.232.81.255254
8398.232.82.0/2498.232.82.1 to 98.232.82.25498.232.82.255254
8498.232.83.0/2498.232.83.1 to 98.232.83.25498.232.83.255254
8598.232.84.0/2498.232.84.1 to 98.232.84.25498.232.84.255254
8698.232.85.0/2498.232.85.1 to 98.232.85.25498.232.85.255254
8798.232.86.0/2498.232.86.1 to 98.232.86.25498.232.86.255254
8898.232.87.0/2498.232.87.1 to 98.232.87.25498.232.87.255254
8998.232.88.0/2498.232.88.1 to 98.232.88.25498.232.88.255254
9098.232.89.0/2498.232.89.1 to 98.232.89.25498.232.89.255254
9198.232.90.0/2498.232.90.1 to 98.232.90.25498.232.90.255254
9298.232.91.0/2498.232.91.1 to 98.232.91.25498.232.91.255254
9398.232.92.0/2498.232.92.1 to 98.232.92.25498.232.92.255254
9498.232.93.0/2498.232.93.1 to 98.232.93.25498.232.93.255254
9598.232.94.0/2498.232.94.1 to 98.232.94.25498.232.94.255254
9698.232.95.0/2498.232.95.1 to 98.232.95.25498.232.95.255254
9798.232.96.0/2498.232.96.1 to 98.232.96.25498.232.96.255254
9898.232.97.0/2498.232.97.1 to 98.232.97.25498.232.97.255254
9998.232.98.0/2498.232.98.1 to 98.232.98.25498.232.98.255254
10098.232.99.0/2498.232.99.1 to 98.232.99.25498.232.99.255254
10198.232.100.0/2498.232.100.1 to 98.232.100.25498.232.100.255254
10298.232.101.0/2498.232.101.1 to 98.232.101.25498.232.101.255254
10398.232.102.0/2498.232.102.1 to 98.232.102.25498.232.102.255254
10498.232.103.0/2498.232.103.1 to 98.232.103.25498.232.103.255254
10598.232.104.0/2498.232.104.1 to 98.232.104.25498.232.104.255254
10698.232.105.0/2498.232.105.1 to 98.232.105.25498.232.105.255254
10798.232.106.0/2498.232.106.1 to 98.232.106.25498.232.106.255254
10898.232.107.0/2498.232.107.1 to 98.232.107.25498.232.107.255254
10998.232.108.0/2498.232.108.1 to 98.232.108.25498.232.108.255254
11098.232.109.0/2498.232.109.1 to 98.232.109.25498.232.109.255254
11198.232.110.0/2498.232.110.1 to 98.232.110.25498.232.110.255254
11298.232.111.0/2498.232.111.1 to 98.232.111.25498.232.111.255254
11398.232.112.0/2498.232.112.1 to 98.232.112.25498.232.112.255254
11498.232.113.0/2498.232.113.1 to 98.232.113.25498.232.113.255254
11598.232.114.0/2498.232.114.1 to 98.232.114.25498.232.114.255254
11698.232.115.0/2498.232.115.1 to 98.232.115.25498.232.115.255254
11798.232.116.0/2498.232.116.1 to 98.232.116.25498.232.116.255254
11898.232.117.0/2498.232.117.1 to 98.232.117.25498.232.117.255254
11998.232.118.0/2498.232.118.1 to 98.232.118.25498.232.118.255254
12098.232.119.0/2498.232.119.1 to 98.232.119.25498.232.119.255254
12198.232.120.0/2498.232.120.1 to 98.232.120.25498.232.120.255254
12298.232.121.0/2498.232.121.1 to 98.232.121.25498.232.121.255254
12398.232.122.0/2498.232.122.1 to 98.232.122.25498.232.122.255254
12498.232.123.0/2498.232.123.1 to 98.232.123.25498.232.123.255254
12598.232.124.0/2498.232.124.1 to 98.232.124.25498.232.124.255254
12698.232.125.0/2498.232.125.1 to 98.232.125.25498.232.125.255254
12798.232.126.0/2498.232.126.1 to 98.232.126.25498.232.126.255254
12898.232.127.0/2498.232.127.1 to 98.232.127.25498.232.127.255254
12998.232.128.0/2498.232.128.1 to 98.232.128.25498.232.128.255254
13098.232.129.0/2498.232.129.1 to 98.232.129.25498.232.129.255254
13198.232.130.0/2498.232.130.1 to 98.232.130.25498.232.130.255254
13298.232.131.0/2498.232.131.1 to 98.232.131.25498.232.131.255254
13398.232.132.0/2498.232.132.1 to 98.232.132.25498.232.132.255254
13498.232.133.0/2498.232.133.1 to 98.232.133.25498.232.133.255254
13598.232.134.0/2498.232.134.1 to 98.232.134.25498.232.134.255254
13698.232.135.0/2498.232.135.1 to 98.232.135.25498.232.135.255254
13798.232.136.0/2498.232.136.1 to 98.232.136.25498.232.136.255254
13898.232.137.0/2498.232.137.1 to 98.232.137.25498.232.137.255254
13998.232.138.0/2498.232.138.1 to 98.232.138.25498.232.138.255254
14098.232.139.0/2498.232.139.1 to 98.232.139.25498.232.139.255254
14198.232.140.0/2498.232.140.1 to 98.232.140.25498.232.140.255254
14298.232.141.0/2498.232.141.1 to 98.232.141.25498.232.141.255254
14398.232.142.0/2498.232.142.1 to 98.232.142.25498.232.142.255254
14498.232.143.0/2498.232.143.1 to 98.232.143.25498.232.143.255254
14598.232.144.0/2498.232.144.1 to 98.232.144.25498.232.144.255254
14698.232.145.0/2498.232.145.1 to 98.232.145.25498.232.145.255254
14798.232.146.0/2498.232.146.1 to 98.232.146.25498.232.146.255254
14898.232.147.0/2498.232.147.1 to 98.232.147.25498.232.147.255254
14998.232.148.0/2498.232.148.1 to 98.232.148.25498.232.148.255254
15098.232.149.0/2498.232.149.1 to 98.232.149.25498.232.149.255254
15198.232.150.0/2498.232.150.1 to 98.232.150.25498.232.150.255254
15298.232.151.0/2498.232.151.1 to 98.232.151.25498.232.151.255254
15398.232.152.0/2498.232.152.1 to 98.232.152.25498.232.152.255254
15498.232.153.0/2498.232.153.1 to 98.232.153.25498.232.153.255254
15598.232.154.0/2498.232.154.1 to 98.232.154.25498.232.154.255254
15698.232.155.0/2498.232.155.1 to 98.232.155.25498.232.155.255254
15798.232.156.0/2498.232.156.1 to 98.232.156.25498.232.156.255254
15898.232.157.0/2498.232.157.1 to 98.232.157.25498.232.157.255254
15998.232.158.0/2498.232.158.1 to 98.232.158.25498.232.158.255254
16098.232.159.0/2498.232.159.1 to 98.232.159.25498.232.159.255254
16198.232.160.0/2498.232.160.1 to 98.232.160.25498.232.160.255254
16298.232.161.0/2498.232.161.1 to 98.232.161.25498.232.161.255254
16398.232.162.0/2498.232.162.1 to 98.232.162.25498.232.162.255254
16498.232.163.0/2498.232.163.1 to 98.232.163.25498.232.163.255254
16598.232.164.0/2498.232.164.1 to 98.232.164.25498.232.164.255254
16698.232.165.0/2498.232.165.1 to 98.232.165.25498.232.165.255254
16798.232.166.0/2498.232.166.1 to 98.232.166.25498.232.166.255254
16898.232.167.0/2498.232.167.1 to 98.232.167.25498.232.167.255254
16998.232.168.0/2498.232.168.1 to 98.232.168.25498.232.168.255254
17098.232.169.0/2498.232.169.1 to 98.232.169.25498.232.169.255254
17198.232.170.0/2498.232.170.1 to 98.232.170.25498.232.170.255254
17298.232.171.0/2498.232.171.1 to 98.232.171.25498.232.171.255254
17398.232.172.0/2498.232.172.1 to 98.232.172.25498.232.172.255254
17498.232.173.0/2498.232.173.1 to 98.232.173.25498.232.173.255254
17598.232.174.0/2498.232.174.1 to 98.232.174.25498.232.174.255254
17698.232.175.0/2498.232.175.1 to 98.232.175.25498.232.175.255254
17798.232.176.0/2498.232.176.1 to 98.232.176.25498.232.176.255254
17898.232.177.0/2498.232.177.1 to 98.232.177.25498.232.177.255254
17998.232.178.0/2498.232.178.1 to 98.232.178.25498.232.178.255254
18098.232.179.0/2498.232.179.1 to 98.232.179.25498.232.179.255254
18198.232.180.0/2498.232.180.1 to 98.232.180.25498.232.180.255254
18298.232.181.0/2498.232.181.1 to 98.232.181.25498.232.181.255254
18398.232.182.0/2498.232.182.1 to 98.232.182.25498.232.182.255254
18498.232.183.0/2498.232.183.1 to 98.232.183.25498.232.183.255254
18598.232.184.0/2498.232.184.1 to 98.232.184.25498.232.184.255254
18698.232.185.0/2498.232.185.1 to 98.232.185.25498.232.185.255254
18798.232.186.0/2498.232.186.1 to 98.232.186.25498.232.186.255254
18898.232.187.0/2498.232.187.1 to 98.232.187.25498.232.187.255254
18998.232.188.0/2498.232.188.1 to 98.232.188.25498.232.188.255254
19098.232.189.0/2498.232.189.1 to 98.232.189.25498.232.189.255254
19198.232.190.0/2498.232.190.1 to 98.232.190.25498.232.190.255254
19298.232.191.0/2498.232.191.1 to 98.232.191.25498.232.191.255254
19398.232.192.0/2498.232.192.1 to 98.232.192.25498.232.192.255254
19498.232.193.0/2498.232.193.1 to 98.232.193.25498.232.193.255254
19598.232.194.0/2498.232.194.1 to 98.232.194.25498.232.194.255254
19698.232.195.0/2498.232.195.1 to 98.232.195.25498.232.195.255254
19798.232.196.0/2498.232.196.1 to 98.232.196.25498.232.196.255254
19898.232.197.0/2498.232.197.1 to 98.232.197.25498.232.197.255254
19998.232.198.0/2498.232.198.1 to 98.232.198.25498.232.198.255254
20098.232.199.0/2498.232.199.1 to 98.232.199.25498.232.199.255254
20198.232.200.0/2498.232.200.1 to 98.232.200.25498.232.200.255254
20298.232.201.0/2498.232.201.1 to 98.232.201.25498.232.201.255254
20398.232.202.0/2498.232.202.1 to 98.232.202.25498.232.202.255254
20498.232.203.0/2498.232.203.1 to 98.232.203.25498.232.203.255254
20598.232.204.0/2498.232.204.1 to 98.232.204.25498.232.204.255254
20698.232.205.0/2498.232.205.1 to 98.232.205.25498.232.205.255254
20798.232.206.0/2498.232.206.1 to 98.232.206.25498.232.206.255254
20898.232.207.0/2498.232.207.1 to 98.232.207.25498.232.207.255254
20998.232.208.0/2498.232.208.1 to 98.232.208.25498.232.208.255254
21098.232.209.0/2498.232.209.1 to 98.232.209.25498.232.209.255254
21198.232.210.0/2498.232.210.1 to 98.232.210.25498.232.210.255254
21298.232.211.0/2498.232.211.1 to 98.232.211.25498.232.211.255254
21398.232.212.0/2498.232.212.1 to 98.232.212.25498.232.212.255254
21498.232.213.0/2498.232.213.1 to 98.232.213.25498.232.213.255254
21598.232.214.0/2498.232.214.1 to 98.232.214.25498.232.214.255254
21698.232.215.0/2498.232.215.1 to 98.232.215.25498.232.215.255254
21798.232.216.0/2498.232.216.1 to 98.232.216.25498.232.216.255254
21898.232.217.0/2498.232.217.1 to 98.232.217.25498.232.217.255254
21998.232.218.0/2498.232.218.1 to 98.232.218.25498.232.218.255254
22098.232.219.0/2498.232.219.1 to 98.232.219.25498.232.219.255254
22198.232.220.0/2498.232.220.1 to 98.232.220.25498.232.220.255254
22298.232.221.0/2498.232.221.1 to 98.232.221.25498.232.221.255254
22398.232.222.0/2498.232.222.1 to 98.232.222.25498.232.222.255254
22498.232.223.0/2498.232.223.1 to 98.232.223.25498.232.223.255254
22598.232.224.0/2498.232.224.1 to 98.232.224.25498.232.224.255254
22698.232.225.0/2498.232.225.1 to 98.232.225.25498.232.225.255254
22798.232.226.0/2498.232.226.1 to 98.232.226.25498.232.226.255254
22898.232.227.0/2498.232.227.1 to 98.232.227.25498.232.227.255254
22998.232.228.0/2498.232.228.1 to 98.232.228.25498.232.228.255254
23098.232.229.0/2498.232.229.1 to 98.232.229.25498.232.229.255254
23198.232.230.0/2498.232.230.1 to 98.232.230.25498.232.230.255254
23298.232.231.0/2498.232.231.1 to 98.232.231.25498.232.231.255254
23398.232.232.0/2498.232.232.1 to 98.232.232.25498.232.232.255254
23498.232.233.0/2498.232.233.1 to 98.232.233.25498.232.233.255254
23598.232.234.0/2498.232.234.1 to 98.232.234.25498.232.234.255254
23698.232.235.0/2498.232.235.1 to 98.232.235.25498.232.235.255254
23798.232.236.0/2498.232.236.1 to 98.232.236.25498.232.236.255254
23898.232.237.0/2498.232.237.1 to 98.232.237.25498.232.237.255254
23998.232.238.0/2498.232.238.1 to 98.232.238.25498.232.238.255254
24098.232.239.0/2498.232.239.1 to 98.232.239.25498.232.239.255254
24198.232.240.0/2498.232.240.1 to 98.232.240.25498.232.240.255254
24298.232.241.0/2498.232.241.1 to 98.232.241.25498.232.241.255254
24398.232.242.0/2498.232.242.1 to 98.232.242.25498.232.242.255254
24498.232.243.0/2498.232.243.1 to 98.232.243.25498.232.243.255254
24598.232.244.0/2498.232.244.1 to 98.232.244.25498.232.244.255254
24698.232.245.0/2498.232.245.1 to 98.232.245.25498.232.245.255254
24798.232.246.0/2498.232.246.1 to 98.232.246.25498.232.246.255254
24898.232.247.0/2498.232.247.1 to 98.232.247.25498.232.247.255254
24998.232.248.0/2498.232.248.1 to 98.232.248.25498.232.248.255254
25098.232.249.0/2498.232.249.1 to 98.232.249.25498.232.249.255254
25198.232.250.0/2498.232.250.1 to 98.232.250.25498.232.250.255254
25298.232.251.0/2498.232.251.1 to 98.232.251.25498.232.251.255254
25398.232.252.0/2498.232.252.1 to 98.232.252.25498.232.252.255254
25498.232.253.0/2498.232.253.1 to 98.232.253.25498.232.253.255254
25598.232.254.0/2498.232.254.1 to 98.232.254.25498.232.254.255254
25698.232.255.0/2498.232.255.1 to 98.232.255.25498.232.255.255254

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.