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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.

Network99.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
99.232.0.0
Broadcast address
99.235.255.255
First usable
99.232.0.1
Last usable
99.235.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 63E80000 · Integer 1676148736 to 1676410879
Reverse DNS zones
232.99.in-addr.arpa
233.99.in-addr.arpa
234.99.in-addr.arpa
235.99.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100011.11101000.00000000.0000000099.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01100011.11101000.00000000.0000000099.232.0.0
Broadcast01100011.11101011.11111111.1111111199.235.255.255
Split into smaller subnets/24
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

99.232.0.0/14 makes 1,024 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
199.232.0.0/2499.232.0.1 to 99.232.0.25499.232.0.255254
299.232.1.0/2499.232.1.1 to 99.232.1.25499.232.1.255254
399.232.2.0/2499.232.2.1 to 99.232.2.25499.232.2.255254
499.232.3.0/2499.232.3.1 to 99.232.3.25499.232.3.255254
599.232.4.0/2499.232.4.1 to 99.232.4.25499.232.4.255254
699.232.5.0/2499.232.5.1 to 99.232.5.25499.232.5.255254
799.232.6.0/2499.232.6.1 to 99.232.6.25499.232.6.255254
899.232.7.0/2499.232.7.1 to 99.232.7.25499.232.7.255254
999.232.8.0/2499.232.8.1 to 99.232.8.25499.232.8.255254
1099.232.9.0/2499.232.9.1 to 99.232.9.25499.232.9.255254
1199.232.10.0/2499.232.10.1 to 99.232.10.25499.232.10.255254
1299.232.11.0/2499.232.11.1 to 99.232.11.25499.232.11.255254
1399.232.12.0/2499.232.12.1 to 99.232.12.25499.232.12.255254
1499.232.13.0/2499.232.13.1 to 99.232.13.25499.232.13.255254
1599.232.14.0/2499.232.14.1 to 99.232.14.25499.232.14.255254
1699.232.15.0/2499.232.15.1 to 99.232.15.25499.232.15.255254
1799.232.16.0/2499.232.16.1 to 99.232.16.25499.232.16.255254
1899.232.17.0/2499.232.17.1 to 99.232.17.25499.232.17.255254
1999.232.18.0/2499.232.18.1 to 99.232.18.25499.232.18.255254
2099.232.19.0/2499.232.19.1 to 99.232.19.25499.232.19.255254
2199.232.20.0/2499.232.20.1 to 99.232.20.25499.232.20.255254
2299.232.21.0/2499.232.21.1 to 99.232.21.25499.232.21.255254
2399.232.22.0/2499.232.22.1 to 99.232.22.25499.232.22.255254
2499.232.23.0/2499.232.23.1 to 99.232.23.25499.232.23.255254
2599.232.24.0/2499.232.24.1 to 99.232.24.25499.232.24.255254
2699.232.25.0/2499.232.25.1 to 99.232.25.25499.232.25.255254
2799.232.26.0/2499.232.26.1 to 99.232.26.25499.232.26.255254
2899.232.27.0/2499.232.27.1 to 99.232.27.25499.232.27.255254
2999.232.28.0/2499.232.28.1 to 99.232.28.25499.232.28.255254
3099.232.29.0/2499.232.29.1 to 99.232.29.25499.232.29.255254
3199.232.30.0/2499.232.30.1 to 99.232.30.25499.232.30.255254
3299.232.31.0/2499.232.31.1 to 99.232.31.25499.232.31.255254
3399.232.32.0/2499.232.32.1 to 99.232.32.25499.232.32.255254
3499.232.33.0/2499.232.33.1 to 99.232.33.25499.232.33.255254
3599.232.34.0/2499.232.34.1 to 99.232.34.25499.232.34.255254
3699.232.35.0/2499.232.35.1 to 99.232.35.25499.232.35.255254
3799.232.36.0/2499.232.36.1 to 99.232.36.25499.232.36.255254
3899.232.37.0/2499.232.37.1 to 99.232.37.25499.232.37.255254
3999.232.38.0/2499.232.38.1 to 99.232.38.25499.232.38.255254
4099.232.39.0/2499.232.39.1 to 99.232.39.25499.232.39.255254
4199.232.40.0/2499.232.40.1 to 99.232.40.25499.232.40.255254
4299.232.41.0/2499.232.41.1 to 99.232.41.25499.232.41.255254
4399.232.42.0/2499.232.42.1 to 99.232.42.25499.232.42.255254
4499.232.43.0/2499.232.43.1 to 99.232.43.25499.232.43.255254
4599.232.44.0/2499.232.44.1 to 99.232.44.25499.232.44.255254
4699.232.45.0/2499.232.45.1 to 99.232.45.25499.232.45.255254
4799.232.46.0/2499.232.46.1 to 99.232.46.25499.232.46.255254
4899.232.47.0/2499.232.47.1 to 99.232.47.25499.232.47.255254
4999.232.48.0/2499.232.48.1 to 99.232.48.25499.232.48.255254
5099.232.49.0/2499.232.49.1 to 99.232.49.25499.232.49.255254
5199.232.50.0/2499.232.50.1 to 99.232.50.25499.232.50.255254
5299.232.51.0/2499.232.51.1 to 99.232.51.25499.232.51.255254
5399.232.52.0/2499.232.52.1 to 99.232.52.25499.232.52.255254
5499.232.53.0/2499.232.53.1 to 99.232.53.25499.232.53.255254
5599.232.54.0/2499.232.54.1 to 99.232.54.25499.232.54.255254
5699.232.55.0/2499.232.55.1 to 99.232.55.25499.232.55.255254
5799.232.56.0/2499.232.56.1 to 99.232.56.25499.232.56.255254
5899.232.57.0/2499.232.57.1 to 99.232.57.25499.232.57.255254
5999.232.58.0/2499.232.58.1 to 99.232.58.25499.232.58.255254
6099.232.59.0/2499.232.59.1 to 99.232.59.25499.232.59.255254
6199.232.60.0/2499.232.60.1 to 99.232.60.25499.232.60.255254
6299.232.61.0/2499.232.61.1 to 99.232.61.25499.232.61.255254
6399.232.62.0/2499.232.62.1 to 99.232.62.25499.232.62.255254
6499.232.63.0/2499.232.63.1 to 99.232.63.25499.232.63.255254
6599.232.64.0/2499.232.64.1 to 99.232.64.25499.232.64.255254
6699.232.65.0/2499.232.65.1 to 99.232.65.25499.232.65.255254
6799.232.66.0/2499.232.66.1 to 99.232.66.25499.232.66.255254
6899.232.67.0/2499.232.67.1 to 99.232.67.25499.232.67.255254
6999.232.68.0/2499.232.68.1 to 99.232.68.25499.232.68.255254
7099.232.69.0/2499.232.69.1 to 99.232.69.25499.232.69.255254
7199.232.70.0/2499.232.70.1 to 99.232.70.25499.232.70.255254
7299.232.71.0/2499.232.71.1 to 99.232.71.25499.232.71.255254
7399.232.72.0/2499.232.72.1 to 99.232.72.25499.232.72.255254
7499.232.73.0/2499.232.73.1 to 99.232.73.25499.232.73.255254
7599.232.74.0/2499.232.74.1 to 99.232.74.25499.232.74.255254
7699.232.75.0/2499.232.75.1 to 99.232.75.25499.232.75.255254
7799.232.76.0/2499.232.76.1 to 99.232.76.25499.232.76.255254
7899.232.77.0/2499.232.77.1 to 99.232.77.25499.232.77.255254
7999.232.78.0/2499.232.78.1 to 99.232.78.25499.232.78.255254
8099.232.79.0/2499.232.79.1 to 99.232.79.25499.232.79.255254
8199.232.80.0/2499.232.80.1 to 99.232.80.25499.232.80.255254
8299.232.81.0/2499.232.81.1 to 99.232.81.25499.232.81.255254
8399.232.82.0/2499.232.82.1 to 99.232.82.25499.232.82.255254
8499.232.83.0/2499.232.83.1 to 99.232.83.25499.232.83.255254
8599.232.84.0/2499.232.84.1 to 99.232.84.25499.232.84.255254
8699.232.85.0/2499.232.85.1 to 99.232.85.25499.232.85.255254
8799.232.86.0/2499.232.86.1 to 99.232.86.25499.232.86.255254
8899.232.87.0/2499.232.87.1 to 99.232.87.25499.232.87.255254
8999.232.88.0/2499.232.88.1 to 99.232.88.25499.232.88.255254
9099.232.89.0/2499.232.89.1 to 99.232.89.25499.232.89.255254
9199.232.90.0/2499.232.90.1 to 99.232.90.25499.232.90.255254
9299.232.91.0/2499.232.91.1 to 99.232.91.25499.232.91.255254
9399.232.92.0/2499.232.92.1 to 99.232.92.25499.232.92.255254
9499.232.93.0/2499.232.93.1 to 99.232.93.25499.232.93.255254
9599.232.94.0/2499.232.94.1 to 99.232.94.25499.232.94.255254
9699.232.95.0/2499.232.95.1 to 99.232.95.25499.232.95.255254
9799.232.96.0/2499.232.96.1 to 99.232.96.25499.232.96.255254
9899.232.97.0/2499.232.97.1 to 99.232.97.25499.232.97.255254
9999.232.98.0/2499.232.98.1 to 99.232.98.25499.232.98.255254
10099.232.99.0/2499.232.99.1 to 99.232.99.25499.232.99.255254
10199.232.100.0/2499.232.100.1 to 99.232.100.25499.232.100.255254
10299.232.101.0/2499.232.101.1 to 99.232.101.25499.232.101.255254
10399.232.102.0/2499.232.102.1 to 99.232.102.25499.232.102.255254
10499.232.103.0/2499.232.103.1 to 99.232.103.25499.232.103.255254
10599.232.104.0/2499.232.104.1 to 99.232.104.25499.232.104.255254
10699.232.105.0/2499.232.105.1 to 99.232.105.25499.232.105.255254
10799.232.106.0/2499.232.106.1 to 99.232.106.25499.232.106.255254
10899.232.107.0/2499.232.107.1 to 99.232.107.25499.232.107.255254
10999.232.108.0/2499.232.108.1 to 99.232.108.25499.232.108.255254
11099.232.109.0/2499.232.109.1 to 99.232.109.25499.232.109.255254
11199.232.110.0/2499.232.110.1 to 99.232.110.25499.232.110.255254
11299.232.111.0/2499.232.111.1 to 99.232.111.25499.232.111.255254
11399.232.112.0/2499.232.112.1 to 99.232.112.25499.232.112.255254
11499.232.113.0/2499.232.113.1 to 99.232.113.25499.232.113.255254
11599.232.114.0/2499.232.114.1 to 99.232.114.25499.232.114.255254
11699.232.115.0/2499.232.115.1 to 99.232.115.25499.232.115.255254
11799.232.116.0/2499.232.116.1 to 99.232.116.25499.232.116.255254
11899.232.117.0/2499.232.117.1 to 99.232.117.25499.232.117.255254
11999.232.118.0/2499.232.118.1 to 99.232.118.25499.232.118.255254
12099.232.119.0/2499.232.119.1 to 99.232.119.25499.232.119.255254
12199.232.120.0/2499.232.120.1 to 99.232.120.25499.232.120.255254
12299.232.121.0/2499.232.121.1 to 99.232.121.25499.232.121.255254
12399.232.122.0/2499.232.122.1 to 99.232.122.25499.232.122.255254
12499.232.123.0/2499.232.123.1 to 99.232.123.25499.232.123.255254
12599.232.124.0/2499.232.124.1 to 99.232.124.25499.232.124.255254
12699.232.125.0/2499.232.125.1 to 99.232.125.25499.232.125.255254
12799.232.126.0/2499.232.126.1 to 99.232.126.25499.232.126.255254
12899.232.127.0/2499.232.127.1 to 99.232.127.25499.232.127.255254
12999.232.128.0/2499.232.128.1 to 99.232.128.25499.232.128.255254
13099.232.129.0/2499.232.129.1 to 99.232.129.25499.232.129.255254
13199.232.130.0/2499.232.130.1 to 99.232.130.25499.232.130.255254
13299.232.131.0/2499.232.131.1 to 99.232.131.25499.232.131.255254
13399.232.132.0/2499.232.132.1 to 99.232.132.25499.232.132.255254
13499.232.133.0/2499.232.133.1 to 99.232.133.25499.232.133.255254
13599.232.134.0/2499.232.134.1 to 99.232.134.25499.232.134.255254
13699.232.135.0/2499.232.135.1 to 99.232.135.25499.232.135.255254
13799.232.136.0/2499.232.136.1 to 99.232.136.25499.232.136.255254
13899.232.137.0/2499.232.137.1 to 99.232.137.25499.232.137.255254
13999.232.138.0/2499.232.138.1 to 99.232.138.25499.232.138.255254
14099.232.139.0/2499.232.139.1 to 99.232.139.25499.232.139.255254
14199.232.140.0/2499.232.140.1 to 99.232.140.25499.232.140.255254
14299.232.141.0/2499.232.141.1 to 99.232.141.25499.232.141.255254
14399.232.142.0/2499.232.142.1 to 99.232.142.25499.232.142.255254
14499.232.143.0/2499.232.143.1 to 99.232.143.25499.232.143.255254
14599.232.144.0/2499.232.144.1 to 99.232.144.25499.232.144.255254
14699.232.145.0/2499.232.145.1 to 99.232.145.25499.232.145.255254
14799.232.146.0/2499.232.146.1 to 99.232.146.25499.232.146.255254
14899.232.147.0/2499.232.147.1 to 99.232.147.25499.232.147.255254
14999.232.148.0/2499.232.148.1 to 99.232.148.25499.232.148.255254
15099.232.149.0/2499.232.149.1 to 99.232.149.25499.232.149.255254
15199.232.150.0/2499.232.150.1 to 99.232.150.25499.232.150.255254
15299.232.151.0/2499.232.151.1 to 99.232.151.25499.232.151.255254
15399.232.152.0/2499.232.152.1 to 99.232.152.25499.232.152.255254
15499.232.153.0/2499.232.153.1 to 99.232.153.25499.232.153.255254
15599.232.154.0/2499.232.154.1 to 99.232.154.25499.232.154.255254
15699.232.155.0/2499.232.155.1 to 99.232.155.25499.232.155.255254
15799.232.156.0/2499.232.156.1 to 99.232.156.25499.232.156.255254
15899.232.157.0/2499.232.157.1 to 99.232.157.25499.232.157.255254
15999.232.158.0/2499.232.158.1 to 99.232.158.25499.232.158.255254
16099.232.159.0/2499.232.159.1 to 99.232.159.25499.232.159.255254
16199.232.160.0/2499.232.160.1 to 99.232.160.25499.232.160.255254
16299.232.161.0/2499.232.161.1 to 99.232.161.25499.232.161.255254
16399.232.162.0/2499.232.162.1 to 99.232.162.25499.232.162.255254
16499.232.163.0/2499.232.163.1 to 99.232.163.25499.232.163.255254
16599.232.164.0/2499.232.164.1 to 99.232.164.25499.232.164.255254
16699.232.165.0/2499.232.165.1 to 99.232.165.25499.232.165.255254
16799.232.166.0/2499.232.166.1 to 99.232.166.25499.232.166.255254
16899.232.167.0/2499.232.167.1 to 99.232.167.25499.232.167.255254
16999.232.168.0/2499.232.168.1 to 99.232.168.25499.232.168.255254
17099.232.169.0/2499.232.169.1 to 99.232.169.25499.232.169.255254
17199.232.170.0/2499.232.170.1 to 99.232.170.25499.232.170.255254
17299.232.171.0/2499.232.171.1 to 99.232.171.25499.232.171.255254
17399.232.172.0/2499.232.172.1 to 99.232.172.25499.232.172.255254
17499.232.173.0/2499.232.173.1 to 99.232.173.25499.232.173.255254
17599.232.174.0/2499.232.174.1 to 99.232.174.25499.232.174.255254
17699.232.175.0/2499.232.175.1 to 99.232.175.25499.232.175.255254
17799.232.176.0/2499.232.176.1 to 99.232.176.25499.232.176.255254
17899.232.177.0/2499.232.177.1 to 99.232.177.25499.232.177.255254
17999.232.178.0/2499.232.178.1 to 99.232.178.25499.232.178.255254
18099.232.179.0/2499.232.179.1 to 99.232.179.25499.232.179.255254
18199.232.180.0/2499.232.180.1 to 99.232.180.25499.232.180.255254
18299.232.181.0/2499.232.181.1 to 99.232.181.25499.232.181.255254
18399.232.182.0/2499.232.182.1 to 99.232.182.25499.232.182.255254
18499.232.183.0/2499.232.183.1 to 99.232.183.25499.232.183.255254
18599.232.184.0/2499.232.184.1 to 99.232.184.25499.232.184.255254
18699.232.185.0/2499.232.185.1 to 99.232.185.25499.232.185.255254
18799.232.186.0/2499.232.186.1 to 99.232.186.25499.232.186.255254
18899.232.187.0/2499.232.187.1 to 99.232.187.25499.232.187.255254
18999.232.188.0/2499.232.188.1 to 99.232.188.25499.232.188.255254
19099.232.189.0/2499.232.189.1 to 99.232.189.25499.232.189.255254
19199.232.190.0/2499.232.190.1 to 99.232.190.25499.232.190.255254
19299.232.191.0/2499.232.191.1 to 99.232.191.25499.232.191.255254
19399.232.192.0/2499.232.192.1 to 99.232.192.25499.232.192.255254
19499.232.193.0/2499.232.193.1 to 99.232.193.25499.232.193.255254
19599.232.194.0/2499.232.194.1 to 99.232.194.25499.232.194.255254
19699.232.195.0/2499.232.195.1 to 99.232.195.25499.232.195.255254
19799.232.196.0/2499.232.196.1 to 99.232.196.25499.232.196.255254
19899.232.197.0/2499.232.197.1 to 99.232.197.25499.232.197.255254
19999.232.198.0/2499.232.198.1 to 99.232.198.25499.232.198.255254
20099.232.199.0/2499.232.199.1 to 99.232.199.25499.232.199.255254
20199.232.200.0/2499.232.200.1 to 99.232.200.25499.232.200.255254
20299.232.201.0/2499.232.201.1 to 99.232.201.25499.232.201.255254
20399.232.202.0/2499.232.202.1 to 99.232.202.25499.232.202.255254
20499.232.203.0/2499.232.203.1 to 99.232.203.25499.232.203.255254
20599.232.204.0/2499.232.204.1 to 99.232.204.25499.232.204.255254
20699.232.205.0/2499.232.205.1 to 99.232.205.25499.232.205.255254
20799.232.206.0/2499.232.206.1 to 99.232.206.25499.232.206.255254
20899.232.207.0/2499.232.207.1 to 99.232.207.25499.232.207.255254
20999.232.208.0/2499.232.208.1 to 99.232.208.25499.232.208.255254
21099.232.209.0/2499.232.209.1 to 99.232.209.25499.232.209.255254
21199.232.210.0/2499.232.210.1 to 99.232.210.25499.232.210.255254
21299.232.211.0/2499.232.211.1 to 99.232.211.25499.232.211.255254
21399.232.212.0/2499.232.212.1 to 99.232.212.25499.232.212.255254
21499.232.213.0/2499.232.213.1 to 99.232.213.25499.232.213.255254
21599.232.214.0/2499.232.214.1 to 99.232.214.25499.232.214.255254
21699.232.215.0/2499.232.215.1 to 99.232.215.25499.232.215.255254
21799.232.216.0/2499.232.216.1 to 99.232.216.25499.232.216.255254
21899.232.217.0/2499.232.217.1 to 99.232.217.25499.232.217.255254
21999.232.218.0/2499.232.218.1 to 99.232.218.25499.232.218.255254
22099.232.219.0/2499.232.219.1 to 99.232.219.25499.232.219.255254
22199.232.220.0/2499.232.220.1 to 99.232.220.25499.232.220.255254
22299.232.221.0/2499.232.221.1 to 99.232.221.25499.232.221.255254
22399.232.222.0/2499.232.222.1 to 99.232.222.25499.232.222.255254
22499.232.223.0/2499.232.223.1 to 99.232.223.25499.232.223.255254
22599.232.224.0/2499.232.224.1 to 99.232.224.25499.232.224.255254
22699.232.225.0/2499.232.225.1 to 99.232.225.25499.232.225.255254
22799.232.226.0/2499.232.226.1 to 99.232.226.25499.232.226.255254
22899.232.227.0/2499.232.227.1 to 99.232.227.25499.232.227.255254
22999.232.228.0/2499.232.228.1 to 99.232.228.25499.232.228.255254
23099.232.229.0/2499.232.229.1 to 99.232.229.25499.232.229.255254
23199.232.230.0/2499.232.230.1 to 99.232.230.25499.232.230.255254
23299.232.231.0/2499.232.231.1 to 99.232.231.25499.232.231.255254
23399.232.232.0/2499.232.232.1 to 99.232.232.25499.232.232.255254
23499.232.233.0/2499.232.233.1 to 99.232.233.25499.232.233.255254
23599.232.234.0/2499.232.234.1 to 99.232.234.25499.232.234.255254
23699.232.235.0/2499.232.235.1 to 99.232.235.25499.232.235.255254
23799.232.236.0/2499.232.236.1 to 99.232.236.25499.232.236.255254
23899.232.237.0/2499.232.237.1 to 99.232.237.25499.232.237.255254
23999.232.238.0/2499.232.238.1 to 99.232.238.25499.232.238.255254
24099.232.239.0/2499.232.239.1 to 99.232.239.25499.232.239.255254
24199.232.240.0/2499.232.240.1 to 99.232.240.25499.232.240.255254
24299.232.241.0/2499.232.241.1 to 99.232.241.25499.232.241.255254
24399.232.242.0/2499.232.242.1 to 99.232.242.25499.232.242.255254
24499.232.243.0/2499.232.243.1 to 99.232.243.25499.232.243.255254
24599.232.244.0/2499.232.244.1 to 99.232.244.25499.232.244.255254
24699.232.245.0/2499.232.245.1 to 99.232.245.25499.232.245.255254
24799.232.246.0/2499.232.246.1 to 99.232.246.25499.232.246.255254
24899.232.247.0/2499.232.247.1 to 99.232.247.25499.232.247.255254
24999.232.248.0/2499.232.248.1 to 99.232.248.25499.232.248.255254
25099.232.249.0/2499.232.249.1 to 99.232.249.25499.232.249.255254
25199.232.250.0/2499.232.250.1 to 99.232.250.25499.232.250.255254
25299.232.251.0/2499.232.251.1 to 99.232.251.25499.232.251.255254
25399.232.252.0/2499.232.252.1 to 99.232.252.25499.232.252.255254
25499.232.253.0/2499.232.253.1 to 99.232.253.25499.232.253.255254
25599.232.254.0/2499.232.254.1 to 99.232.254.25499.232.254.255254
25699.232.255.0/2499.232.255.1 to 99.232.255.25499.232.255.255254

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.