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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.

Network99.48.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
99.48.0.0
Broadcast address
99.55.255.255
First usable
99.48.0.1
Last usable
99.55.255.254
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 63300000 · Integer 1664090112 to 1664614399
Reverse DNS zones
48.99.in-addr.arpa
49.99.in-addr.arpa
50.99.in-addr.arpa
51.99.in-addr.arpa
52.99.in-addr.arpa
53.99.in-addr.arpa
54.99.in-addr.arpa
55.99.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
Address01100011.00110000.00000000.0000000099.48.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01100011.00110000.00000000.0000000099.48.0.0
Broadcast01100011.00110111.11111111.1111111199.55.255.255
Split into smaller subnets/23
/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)

99.48.0.0/13 makes 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
199.48.0.0/2399.48.0.1 to 99.48.1.25499.48.1.255510
299.48.2.0/2399.48.2.1 to 99.48.3.25499.48.3.255510
399.48.4.0/2399.48.4.1 to 99.48.5.25499.48.5.255510
499.48.6.0/2399.48.6.1 to 99.48.7.25499.48.7.255510
599.48.8.0/2399.48.8.1 to 99.48.9.25499.48.9.255510
699.48.10.0/2399.48.10.1 to 99.48.11.25499.48.11.255510
799.48.12.0/2399.48.12.1 to 99.48.13.25499.48.13.255510
899.48.14.0/2399.48.14.1 to 99.48.15.25499.48.15.255510
999.48.16.0/2399.48.16.1 to 99.48.17.25499.48.17.255510
1099.48.18.0/2399.48.18.1 to 99.48.19.25499.48.19.255510
1199.48.20.0/2399.48.20.1 to 99.48.21.25499.48.21.255510
1299.48.22.0/2399.48.22.1 to 99.48.23.25499.48.23.255510
1399.48.24.0/2399.48.24.1 to 99.48.25.25499.48.25.255510
1499.48.26.0/2399.48.26.1 to 99.48.27.25499.48.27.255510
1599.48.28.0/2399.48.28.1 to 99.48.29.25499.48.29.255510
1699.48.30.0/2399.48.30.1 to 99.48.31.25499.48.31.255510
1799.48.32.0/2399.48.32.1 to 99.48.33.25499.48.33.255510
1899.48.34.0/2399.48.34.1 to 99.48.35.25499.48.35.255510
1999.48.36.0/2399.48.36.1 to 99.48.37.25499.48.37.255510
2099.48.38.0/2399.48.38.1 to 99.48.39.25499.48.39.255510
2199.48.40.0/2399.48.40.1 to 99.48.41.25499.48.41.255510
2299.48.42.0/2399.48.42.1 to 99.48.43.25499.48.43.255510
2399.48.44.0/2399.48.44.1 to 99.48.45.25499.48.45.255510
2499.48.46.0/2399.48.46.1 to 99.48.47.25499.48.47.255510
2599.48.48.0/2399.48.48.1 to 99.48.49.25499.48.49.255510
2699.48.50.0/2399.48.50.1 to 99.48.51.25499.48.51.255510
2799.48.52.0/2399.48.52.1 to 99.48.53.25499.48.53.255510
2899.48.54.0/2399.48.54.1 to 99.48.55.25499.48.55.255510
2999.48.56.0/2399.48.56.1 to 99.48.57.25499.48.57.255510
3099.48.58.0/2399.48.58.1 to 99.48.59.25499.48.59.255510
3199.48.60.0/2399.48.60.1 to 99.48.61.25499.48.61.255510
3299.48.62.0/2399.48.62.1 to 99.48.63.25499.48.63.255510
3399.48.64.0/2399.48.64.1 to 99.48.65.25499.48.65.255510
3499.48.66.0/2399.48.66.1 to 99.48.67.25499.48.67.255510
3599.48.68.0/2399.48.68.1 to 99.48.69.25499.48.69.255510
3699.48.70.0/2399.48.70.1 to 99.48.71.25499.48.71.255510
3799.48.72.0/2399.48.72.1 to 99.48.73.25499.48.73.255510
3899.48.74.0/2399.48.74.1 to 99.48.75.25499.48.75.255510
3999.48.76.0/2399.48.76.1 to 99.48.77.25499.48.77.255510
4099.48.78.0/2399.48.78.1 to 99.48.79.25499.48.79.255510
4199.48.80.0/2399.48.80.1 to 99.48.81.25499.48.81.255510
4299.48.82.0/2399.48.82.1 to 99.48.83.25499.48.83.255510
4399.48.84.0/2399.48.84.1 to 99.48.85.25499.48.85.255510
4499.48.86.0/2399.48.86.1 to 99.48.87.25499.48.87.255510
4599.48.88.0/2399.48.88.1 to 99.48.89.25499.48.89.255510
4699.48.90.0/2399.48.90.1 to 99.48.91.25499.48.91.255510
4799.48.92.0/2399.48.92.1 to 99.48.93.25499.48.93.255510
4899.48.94.0/2399.48.94.1 to 99.48.95.25499.48.95.255510
4999.48.96.0/2399.48.96.1 to 99.48.97.25499.48.97.255510
5099.48.98.0/2399.48.98.1 to 99.48.99.25499.48.99.255510
5199.48.100.0/2399.48.100.1 to 99.48.101.25499.48.101.255510
5299.48.102.0/2399.48.102.1 to 99.48.103.25499.48.103.255510
5399.48.104.0/2399.48.104.1 to 99.48.105.25499.48.105.255510
5499.48.106.0/2399.48.106.1 to 99.48.107.25499.48.107.255510
5599.48.108.0/2399.48.108.1 to 99.48.109.25499.48.109.255510
5699.48.110.0/2399.48.110.1 to 99.48.111.25499.48.111.255510
5799.48.112.0/2399.48.112.1 to 99.48.113.25499.48.113.255510
5899.48.114.0/2399.48.114.1 to 99.48.115.25499.48.115.255510
5999.48.116.0/2399.48.116.1 to 99.48.117.25499.48.117.255510
6099.48.118.0/2399.48.118.1 to 99.48.119.25499.48.119.255510
6199.48.120.0/2399.48.120.1 to 99.48.121.25499.48.121.255510
6299.48.122.0/2399.48.122.1 to 99.48.123.25499.48.123.255510
6399.48.124.0/2399.48.124.1 to 99.48.125.25499.48.125.255510
6499.48.126.0/2399.48.126.1 to 99.48.127.25499.48.127.255510
6599.48.128.0/2399.48.128.1 to 99.48.129.25499.48.129.255510
6699.48.130.0/2399.48.130.1 to 99.48.131.25499.48.131.255510
6799.48.132.0/2399.48.132.1 to 99.48.133.25499.48.133.255510
6899.48.134.0/2399.48.134.1 to 99.48.135.25499.48.135.255510
6999.48.136.0/2399.48.136.1 to 99.48.137.25499.48.137.255510
7099.48.138.0/2399.48.138.1 to 99.48.139.25499.48.139.255510
7199.48.140.0/2399.48.140.1 to 99.48.141.25499.48.141.255510
7299.48.142.0/2399.48.142.1 to 99.48.143.25499.48.143.255510
7399.48.144.0/2399.48.144.1 to 99.48.145.25499.48.145.255510
7499.48.146.0/2399.48.146.1 to 99.48.147.25499.48.147.255510
7599.48.148.0/2399.48.148.1 to 99.48.149.25499.48.149.255510
7699.48.150.0/2399.48.150.1 to 99.48.151.25499.48.151.255510
7799.48.152.0/2399.48.152.1 to 99.48.153.25499.48.153.255510
7899.48.154.0/2399.48.154.1 to 99.48.155.25499.48.155.255510
7999.48.156.0/2399.48.156.1 to 99.48.157.25499.48.157.255510
8099.48.158.0/2399.48.158.1 to 99.48.159.25499.48.159.255510
8199.48.160.0/2399.48.160.1 to 99.48.161.25499.48.161.255510
8299.48.162.0/2399.48.162.1 to 99.48.163.25499.48.163.255510
8399.48.164.0/2399.48.164.1 to 99.48.165.25499.48.165.255510
8499.48.166.0/2399.48.166.1 to 99.48.167.25499.48.167.255510
8599.48.168.0/2399.48.168.1 to 99.48.169.25499.48.169.255510
8699.48.170.0/2399.48.170.1 to 99.48.171.25499.48.171.255510
8799.48.172.0/2399.48.172.1 to 99.48.173.25499.48.173.255510
8899.48.174.0/2399.48.174.1 to 99.48.175.25499.48.175.255510
8999.48.176.0/2399.48.176.1 to 99.48.177.25499.48.177.255510
9099.48.178.0/2399.48.178.1 to 99.48.179.25499.48.179.255510
9199.48.180.0/2399.48.180.1 to 99.48.181.25499.48.181.255510
9299.48.182.0/2399.48.182.1 to 99.48.183.25499.48.183.255510
9399.48.184.0/2399.48.184.1 to 99.48.185.25499.48.185.255510
9499.48.186.0/2399.48.186.1 to 99.48.187.25499.48.187.255510
9599.48.188.0/2399.48.188.1 to 99.48.189.25499.48.189.255510
9699.48.190.0/2399.48.190.1 to 99.48.191.25499.48.191.255510
9799.48.192.0/2399.48.192.1 to 99.48.193.25499.48.193.255510
9899.48.194.0/2399.48.194.1 to 99.48.195.25499.48.195.255510
9999.48.196.0/2399.48.196.1 to 99.48.197.25499.48.197.255510
10099.48.198.0/2399.48.198.1 to 99.48.199.25499.48.199.255510
10199.48.200.0/2399.48.200.1 to 99.48.201.25499.48.201.255510
10299.48.202.0/2399.48.202.1 to 99.48.203.25499.48.203.255510
10399.48.204.0/2399.48.204.1 to 99.48.205.25499.48.205.255510
10499.48.206.0/2399.48.206.1 to 99.48.207.25499.48.207.255510
10599.48.208.0/2399.48.208.1 to 99.48.209.25499.48.209.255510
10699.48.210.0/2399.48.210.1 to 99.48.211.25499.48.211.255510
10799.48.212.0/2399.48.212.1 to 99.48.213.25499.48.213.255510
10899.48.214.0/2399.48.214.1 to 99.48.215.25499.48.215.255510
10999.48.216.0/2399.48.216.1 to 99.48.217.25499.48.217.255510
11099.48.218.0/2399.48.218.1 to 99.48.219.25499.48.219.255510
11199.48.220.0/2399.48.220.1 to 99.48.221.25499.48.221.255510
11299.48.222.0/2399.48.222.1 to 99.48.223.25499.48.223.255510
11399.48.224.0/2399.48.224.1 to 99.48.225.25499.48.225.255510
11499.48.226.0/2399.48.226.1 to 99.48.227.25499.48.227.255510
11599.48.228.0/2399.48.228.1 to 99.48.229.25499.48.229.255510
11699.48.230.0/2399.48.230.1 to 99.48.231.25499.48.231.255510
11799.48.232.0/2399.48.232.1 to 99.48.233.25499.48.233.255510
11899.48.234.0/2399.48.234.1 to 99.48.235.25499.48.235.255510
11999.48.236.0/2399.48.236.1 to 99.48.237.25499.48.237.255510
12099.48.238.0/2399.48.238.1 to 99.48.239.25499.48.239.255510
12199.48.240.0/2399.48.240.1 to 99.48.241.25499.48.241.255510
12299.48.242.0/2399.48.242.1 to 99.48.243.25499.48.243.255510
12399.48.244.0/2399.48.244.1 to 99.48.245.25499.48.245.255510
12499.48.246.0/2399.48.246.1 to 99.48.247.25499.48.247.255510
12599.48.248.0/2399.48.248.1 to 99.48.249.25499.48.249.255510
12699.48.250.0/2399.48.250.1 to 99.48.251.25499.48.251.255510
12799.48.252.0/2399.48.252.1 to 99.48.253.25499.48.253.255510
12899.48.254.0/2399.48.254.1 to 99.48.255.25499.48.255.255510
12999.49.0.0/2399.49.0.1 to 99.49.1.25499.49.1.255510
13099.49.2.0/2399.49.2.1 to 99.49.3.25499.49.3.255510
13199.49.4.0/2399.49.4.1 to 99.49.5.25499.49.5.255510
13299.49.6.0/2399.49.6.1 to 99.49.7.25499.49.7.255510
13399.49.8.0/2399.49.8.1 to 99.49.9.25499.49.9.255510
13499.49.10.0/2399.49.10.1 to 99.49.11.25499.49.11.255510
13599.49.12.0/2399.49.12.1 to 99.49.13.25499.49.13.255510
13699.49.14.0/2399.49.14.1 to 99.49.15.25499.49.15.255510
13799.49.16.0/2399.49.16.1 to 99.49.17.25499.49.17.255510
13899.49.18.0/2399.49.18.1 to 99.49.19.25499.49.19.255510
13999.49.20.0/2399.49.20.1 to 99.49.21.25499.49.21.255510
14099.49.22.0/2399.49.22.1 to 99.49.23.25499.49.23.255510
14199.49.24.0/2399.49.24.1 to 99.49.25.25499.49.25.255510
14299.49.26.0/2399.49.26.1 to 99.49.27.25499.49.27.255510
14399.49.28.0/2399.49.28.1 to 99.49.29.25499.49.29.255510
14499.49.30.0/2399.49.30.1 to 99.49.31.25499.49.31.255510
14599.49.32.0/2399.49.32.1 to 99.49.33.25499.49.33.255510
14699.49.34.0/2399.49.34.1 to 99.49.35.25499.49.35.255510
14799.49.36.0/2399.49.36.1 to 99.49.37.25499.49.37.255510
14899.49.38.0/2399.49.38.1 to 99.49.39.25499.49.39.255510
14999.49.40.0/2399.49.40.1 to 99.49.41.25499.49.41.255510
15099.49.42.0/2399.49.42.1 to 99.49.43.25499.49.43.255510
15199.49.44.0/2399.49.44.1 to 99.49.45.25499.49.45.255510
15299.49.46.0/2399.49.46.1 to 99.49.47.25499.49.47.255510
15399.49.48.0/2399.49.48.1 to 99.49.49.25499.49.49.255510
15499.49.50.0/2399.49.50.1 to 99.49.51.25499.49.51.255510
15599.49.52.0/2399.49.52.1 to 99.49.53.25499.49.53.255510
15699.49.54.0/2399.49.54.1 to 99.49.55.25499.49.55.255510
15799.49.56.0/2399.49.56.1 to 99.49.57.25499.49.57.255510
15899.49.58.0/2399.49.58.1 to 99.49.59.25499.49.59.255510
15999.49.60.0/2399.49.60.1 to 99.49.61.25499.49.61.255510
16099.49.62.0/2399.49.62.1 to 99.49.63.25499.49.63.255510
16199.49.64.0/2399.49.64.1 to 99.49.65.25499.49.65.255510
16299.49.66.0/2399.49.66.1 to 99.49.67.25499.49.67.255510
16399.49.68.0/2399.49.68.1 to 99.49.69.25499.49.69.255510
16499.49.70.0/2399.49.70.1 to 99.49.71.25499.49.71.255510
16599.49.72.0/2399.49.72.1 to 99.49.73.25499.49.73.255510
16699.49.74.0/2399.49.74.1 to 99.49.75.25499.49.75.255510
16799.49.76.0/2399.49.76.1 to 99.49.77.25499.49.77.255510
16899.49.78.0/2399.49.78.1 to 99.49.79.25499.49.79.255510
16999.49.80.0/2399.49.80.1 to 99.49.81.25499.49.81.255510
17099.49.82.0/2399.49.82.1 to 99.49.83.25499.49.83.255510
17199.49.84.0/2399.49.84.1 to 99.49.85.25499.49.85.255510
17299.49.86.0/2399.49.86.1 to 99.49.87.25499.49.87.255510
17399.49.88.0/2399.49.88.1 to 99.49.89.25499.49.89.255510
17499.49.90.0/2399.49.90.1 to 99.49.91.25499.49.91.255510
17599.49.92.0/2399.49.92.1 to 99.49.93.25499.49.93.255510
17699.49.94.0/2399.49.94.1 to 99.49.95.25499.49.95.255510
17799.49.96.0/2399.49.96.1 to 99.49.97.25499.49.97.255510
17899.49.98.0/2399.49.98.1 to 99.49.99.25499.49.99.255510
17999.49.100.0/2399.49.100.1 to 99.49.101.25499.49.101.255510
18099.49.102.0/2399.49.102.1 to 99.49.103.25499.49.103.255510
18199.49.104.0/2399.49.104.1 to 99.49.105.25499.49.105.255510
18299.49.106.0/2399.49.106.1 to 99.49.107.25499.49.107.255510
18399.49.108.0/2399.49.108.1 to 99.49.109.25499.49.109.255510
18499.49.110.0/2399.49.110.1 to 99.49.111.25499.49.111.255510
18599.49.112.0/2399.49.112.1 to 99.49.113.25499.49.113.255510
18699.49.114.0/2399.49.114.1 to 99.49.115.25499.49.115.255510
18799.49.116.0/2399.49.116.1 to 99.49.117.25499.49.117.255510
18899.49.118.0/2399.49.118.1 to 99.49.119.25499.49.119.255510
18999.49.120.0/2399.49.120.1 to 99.49.121.25499.49.121.255510
19099.49.122.0/2399.49.122.1 to 99.49.123.25499.49.123.255510
19199.49.124.0/2399.49.124.1 to 99.49.125.25499.49.125.255510
19299.49.126.0/2399.49.126.1 to 99.49.127.25499.49.127.255510
19399.49.128.0/2399.49.128.1 to 99.49.129.25499.49.129.255510
19499.49.130.0/2399.49.130.1 to 99.49.131.25499.49.131.255510
19599.49.132.0/2399.49.132.1 to 99.49.133.25499.49.133.255510
19699.49.134.0/2399.49.134.1 to 99.49.135.25499.49.135.255510
19799.49.136.0/2399.49.136.1 to 99.49.137.25499.49.137.255510
19899.49.138.0/2399.49.138.1 to 99.49.139.25499.49.139.255510
19999.49.140.0/2399.49.140.1 to 99.49.141.25499.49.141.255510
20099.49.142.0/2399.49.142.1 to 99.49.143.25499.49.143.255510
20199.49.144.0/2399.49.144.1 to 99.49.145.25499.49.145.255510
20299.49.146.0/2399.49.146.1 to 99.49.147.25499.49.147.255510
20399.49.148.0/2399.49.148.1 to 99.49.149.25499.49.149.255510
20499.49.150.0/2399.49.150.1 to 99.49.151.25499.49.151.255510
20599.49.152.0/2399.49.152.1 to 99.49.153.25499.49.153.255510
20699.49.154.0/2399.49.154.1 to 99.49.155.25499.49.155.255510
20799.49.156.0/2399.49.156.1 to 99.49.157.25499.49.157.255510
20899.49.158.0/2399.49.158.1 to 99.49.159.25499.49.159.255510
20999.49.160.0/2399.49.160.1 to 99.49.161.25499.49.161.255510
21099.49.162.0/2399.49.162.1 to 99.49.163.25499.49.163.255510
21199.49.164.0/2399.49.164.1 to 99.49.165.25499.49.165.255510
21299.49.166.0/2399.49.166.1 to 99.49.167.25499.49.167.255510
21399.49.168.0/2399.49.168.1 to 99.49.169.25499.49.169.255510
21499.49.170.0/2399.49.170.1 to 99.49.171.25499.49.171.255510
21599.49.172.0/2399.49.172.1 to 99.49.173.25499.49.173.255510
21699.49.174.0/2399.49.174.1 to 99.49.175.25499.49.175.255510
21799.49.176.0/2399.49.176.1 to 99.49.177.25499.49.177.255510
21899.49.178.0/2399.49.178.1 to 99.49.179.25499.49.179.255510
21999.49.180.0/2399.49.180.1 to 99.49.181.25499.49.181.255510
22099.49.182.0/2399.49.182.1 to 99.49.183.25499.49.183.255510
22199.49.184.0/2399.49.184.1 to 99.49.185.25499.49.185.255510
22299.49.186.0/2399.49.186.1 to 99.49.187.25499.49.187.255510
22399.49.188.0/2399.49.188.1 to 99.49.189.25499.49.189.255510
22499.49.190.0/2399.49.190.1 to 99.49.191.25499.49.191.255510
22599.49.192.0/2399.49.192.1 to 99.49.193.25499.49.193.255510
22699.49.194.0/2399.49.194.1 to 99.49.195.25499.49.195.255510
22799.49.196.0/2399.49.196.1 to 99.49.197.25499.49.197.255510
22899.49.198.0/2399.49.198.1 to 99.49.199.25499.49.199.255510
22999.49.200.0/2399.49.200.1 to 99.49.201.25499.49.201.255510
23099.49.202.0/2399.49.202.1 to 99.49.203.25499.49.203.255510
23199.49.204.0/2399.49.204.1 to 99.49.205.25499.49.205.255510
23299.49.206.0/2399.49.206.1 to 99.49.207.25499.49.207.255510
23399.49.208.0/2399.49.208.1 to 99.49.209.25499.49.209.255510
23499.49.210.0/2399.49.210.1 to 99.49.211.25499.49.211.255510
23599.49.212.0/2399.49.212.1 to 99.49.213.25499.49.213.255510
23699.49.214.0/2399.49.214.1 to 99.49.215.25499.49.215.255510
23799.49.216.0/2399.49.216.1 to 99.49.217.25499.49.217.255510
23899.49.218.0/2399.49.218.1 to 99.49.219.25499.49.219.255510
23999.49.220.0/2399.49.220.1 to 99.49.221.25499.49.221.255510
24099.49.222.0/2399.49.222.1 to 99.49.223.25499.49.223.255510
24199.49.224.0/2399.49.224.1 to 99.49.225.25499.49.225.255510
24299.49.226.0/2399.49.226.1 to 99.49.227.25499.49.227.255510
24399.49.228.0/2399.49.228.1 to 99.49.229.25499.49.229.255510
24499.49.230.0/2399.49.230.1 to 99.49.231.25499.49.231.255510
24599.49.232.0/2399.49.232.1 to 99.49.233.25499.49.233.255510
24699.49.234.0/2399.49.234.1 to 99.49.235.25499.49.235.255510
24799.49.236.0/2399.49.236.1 to 99.49.237.25499.49.237.255510
24899.49.238.0/2399.49.238.1 to 99.49.239.25499.49.239.255510
24999.49.240.0/2399.49.240.1 to 99.49.241.25499.49.241.255510
25099.49.242.0/2399.49.242.1 to 99.49.243.25499.49.243.255510
25199.49.244.0/2399.49.244.1 to 99.49.245.25499.49.245.255510
25299.49.246.0/2399.49.246.1 to 99.49.247.25499.49.247.255510
25399.49.248.0/2399.49.248.1 to 99.49.249.25499.49.249.255510
25499.49.250.0/2399.49.250.1 to 99.49.251.25499.49.251.255510
25599.49.252.0/2399.49.252.1 to 99.49.253.25499.49.253.255510
25699.49.254.0/2399.49.254.1 to 99.49.255.25499.49.255.255510

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.