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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.

Network58.8.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
58.8.0.0
Broadcast address
58.15.255.255
First usable
58.8.0.1
Last usable
58.15.255.254
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 3A080000 · Integer 973602816 to 974127103
Reverse DNS zones
8.58.in-addr.arpa
9.58.in-addr.arpa
10.58.in-addr.arpa
11.58.in-addr.arpa
12.58.in-addr.arpa
13.58.in-addr.arpa
14.58.in-addr.arpa
15.58.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
Address00111010.00001000.00000000.0000000058.8.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network00111010.00001000.00000000.0000000058.8.0.0
Broadcast00111010.00001111.11111111.1111111158.15.255.255
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)

58.8.0.0/13 makes 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
158.8.0.0/2358.8.0.1 to 58.8.1.25458.8.1.255510
258.8.2.0/2358.8.2.1 to 58.8.3.25458.8.3.255510
358.8.4.0/2358.8.4.1 to 58.8.5.25458.8.5.255510
458.8.6.0/2358.8.6.1 to 58.8.7.25458.8.7.255510
558.8.8.0/2358.8.8.1 to 58.8.9.25458.8.9.255510
658.8.10.0/2358.8.10.1 to 58.8.11.25458.8.11.255510
758.8.12.0/2358.8.12.1 to 58.8.13.25458.8.13.255510
858.8.14.0/2358.8.14.1 to 58.8.15.25458.8.15.255510
958.8.16.0/2358.8.16.1 to 58.8.17.25458.8.17.255510
1058.8.18.0/2358.8.18.1 to 58.8.19.25458.8.19.255510
1158.8.20.0/2358.8.20.1 to 58.8.21.25458.8.21.255510
1258.8.22.0/2358.8.22.1 to 58.8.23.25458.8.23.255510
1358.8.24.0/2358.8.24.1 to 58.8.25.25458.8.25.255510
1458.8.26.0/2358.8.26.1 to 58.8.27.25458.8.27.255510
1558.8.28.0/2358.8.28.1 to 58.8.29.25458.8.29.255510
1658.8.30.0/2358.8.30.1 to 58.8.31.25458.8.31.255510
1758.8.32.0/2358.8.32.1 to 58.8.33.25458.8.33.255510
1858.8.34.0/2358.8.34.1 to 58.8.35.25458.8.35.255510
1958.8.36.0/2358.8.36.1 to 58.8.37.25458.8.37.255510
2058.8.38.0/2358.8.38.1 to 58.8.39.25458.8.39.255510
2158.8.40.0/2358.8.40.1 to 58.8.41.25458.8.41.255510
2258.8.42.0/2358.8.42.1 to 58.8.43.25458.8.43.255510
2358.8.44.0/2358.8.44.1 to 58.8.45.25458.8.45.255510
2458.8.46.0/2358.8.46.1 to 58.8.47.25458.8.47.255510
2558.8.48.0/2358.8.48.1 to 58.8.49.25458.8.49.255510
2658.8.50.0/2358.8.50.1 to 58.8.51.25458.8.51.255510
2758.8.52.0/2358.8.52.1 to 58.8.53.25458.8.53.255510
2858.8.54.0/2358.8.54.1 to 58.8.55.25458.8.55.255510
2958.8.56.0/2358.8.56.1 to 58.8.57.25458.8.57.255510
3058.8.58.0/2358.8.58.1 to 58.8.59.25458.8.59.255510
3158.8.60.0/2358.8.60.1 to 58.8.61.25458.8.61.255510
3258.8.62.0/2358.8.62.1 to 58.8.63.25458.8.63.255510
3358.8.64.0/2358.8.64.1 to 58.8.65.25458.8.65.255510
3458.8.66.0/2358.8.66.1 to 58.8.67.25458.8.67.255510
3558.8.68.0/2358.8.68.1 to 58.8.69.25458.8.69.255510
3658.8.70.0/2358.8.70.1 to 58.8.71.25458.8.71.255510
3758.8.72.0/2358.8.72.1 to 58.8.73.25458.8.73.255510
3858.8.74.0/2358.8.74.1 to 58.8.75.25458.8.75.255510
3958.8.76.0/2358.8.76.1 to 58.8.77.25458.8.77.255510
4058.8.78.0/2358.8.78.1 to 58.8.79.25458.8.79.255510
4158.8.80.0/2358.8.80.1 to 58.8.81.25458.8.81.255510
4258.8.82.0/2358.8.82.1 to 58.8.83.25458.8.83.255510
4358.8.84.0/2358.8.84.1 to 58.8.85.25458.8.85.255510
4458.8.86.0/2358.8.86.1 to 58.8.87.25458.8.87.255510
4558.8.88.0/2358.8.88.1 to 58.8.89.25458.8.89.255510
4658.8.90.0/2358.8.90.1 to 58.8.91.25458.8.91.255510
4758.8.92.0/2358.8.92.1 to 58.8.93.25458.8.93.255510
4858.8.94.0/2358.8.94.1 to 58.8.95.25458.8.95.255510
4958.8.96.0/2358.8.96.1 to 58.8.97.25458.8.97.255510
5058.8.98.0/2358.8.98.1 to 58.8.99.25458.8.99.255510
5158.8.100.0/2358.8.100.1 to 58.8.101.25458.8.101.255510
5258.8.102.0/2358.8.102.1 to 58.8.103.25458.8.103.255510
5358.8.104.0/2358.8.104.1 to 58.8.105.25458.8.105.255510
5458.8.106.0/2358.8.106.1 to 58.8.107.25458.8.107.255510
5558.8.108.0/2358.8.108.1 to 58.8.109.25458.8.109.255510
5658.8.110.0/2358.8.110.1 to 58.8.111.25458.8.111.255510
5758.8.112.0/2358.8.112.1 to 58.8.113.25458.8.113.255510
5858.8.114.0/2358.8.114.1 to 58.8.115.25458.8.115.255510
5958.8.116.0/2358.8.116.1 to 58.8.117.25458.8.117.255510
6058.8.118.0/2358.8.118.1 to 58.8.119.25458.8.119.255510
6158.8.120.0/2358.8.120.1 to 58.8.121.25458.8.121.255510
6258.8.122.0/2358.8.122.1 to 58.8.123.25458.8.123.255510
6358.8.124.0/2358.8.124.1 to 58.8.125.25458.8.125.255510
6458.8.126.0/2358.8.126.1 to 58.8.127.25458.8.127.255510
6558.8.128.0/2358.8.128.1 to 58.8.129.25458.8.129.255510
6658.8.130.0/2358.8.130.1 to 58.8.131.25458.8.131.255510
6758.8.132.0/2358.8.132.1 to 58.8.133.25458.8.133.255510
6858.8.134.0/2358.8.134.1 to 58.8.135.25458.8.135.255510
6958.8.136.0/2358.8.136.1 to 58.8.137.25458.8.137.255510
7058.8.138.0/2358.8.138.1 to 58.8.139.25458.8.139.255510
7158.8.140.0/2358.8.140.1 to 58.8.141.25458.8.141.255510
7258.8.142.0/2358.8.142.1 to 58.8.143.25458.8.143.255510
7358.8.144.0/2358.8.144.1 to 58.8.145.25458.8.145.255510
7458.8.146.0/2358.8.146.1 to 58.8.147.25458.8.147.255510
7558.8.148.0/2358.8.148.1 to 58.8.149.25458.8.149.255510
7658.8.150.0/2358.8.150.1 to 58.8.151.25458.8.151.255510
7758.8.152.0/2358.8.152.1 to 58.8.153.25458.8.153.255510
7858.8.154.0/2358.8.154.1 to 58.8.155.25458.8.155.255510
7958.8.156.0/2358.8.156.1 to 58.8.157.25458.8.157.255510
8058.8.158.0/2358.8.158.1 to 58.8.159.25458.8.159.255510
8158.8.160.0/2358.8.160.1 to 58.8.161.25458.8.161.255510
8258.8.162.0/2358.8.162.1 to 58.8.163.25458.8.163.255510
8358.8.164.0/2358.8.164.1 to 58.8.165.25458.8.165.255510
8458.8.166.0/2358.8.166.1 to 58.8.167.25458.8.167.255510
8558.8.168.0/2358.8.168.1 to 58.8.169.25458.8.169.255510
8658.8.170.0/2358.8.170.1 to 58.8.171.25458.8.171.255510
8758.8.172.0/2358.8.172.1 to 58.8.173.25458.8.173.255510
8858.8.174.0/2358.8.174.1 to 58.8.175.25458.8.175.255510
8958.8.176.0/2358.8.176.1 to 58.8.177.25458.8.177.255510
9058.8.178.0/2358.8.178.1 to 58.8.179.25458.8.179.255510
9158.8.180.0/2358.8.180.1 to 58.8.181.25458.8.181.255510
9258.8.182.0/2358.8.182.1 to 58.8.183.25458.8.183.255510
9358.8.184.0/2358.8.184.1 to 58.8.185.25458.8.185.255510
9458.8.186.0/2358.8.186.1 to 58.8.187.25458.8.187.255510
9558.8.188.0/2358.8.188.1 to 58.8.189.25458.8.189.255510
9658.8.190.0/2358.8.190.1 to 58.8.191.25458.8.191.255510
9758.8.192.0/2358.8.192.1 to 58.8.193.25458.8.193.255510
9858.8.194.0/2358.8.194.1 to 58.8.195.25458.8.195.255510
9958.8.196.0/2358.8.196.1 to 58.8.197.25458.8.197.255510
10058.8.198.0/2358.8.198.1 to 58.8.199.25458.8.199.255510
10158.8.200.0/2358.8.200.1 to 58.8.201.25458.8.201.255510
10258.8.202.0/2358.8.202.1 to 58.8.203.25458.8.203.255510
10358.8.204.0/2358.8.204.1 to 58.8.205.25458.8.205.255510
10458.8.206.0/2358.8.206.1 to 58.8.207.25458.8.207.255510
10558.8.208.0/2358.8.208.1 to 58.8.209.25458.8.209.255510
10658.8.210.0/2358.8.210.1 to 58.8.211.25458.8.211.255510
10758.8.212.0/2358.8.212.1 to 58.8.213.25458.8.213.255510
10858.8.214.0/2358.8.214.1 to 58.8.215.25458.8.215.255510
10958.8.216.0/2358.8.216.1 to 58.8.217.25458.8.217.255510
11058.8.218.0/2358.8.218.1 to 58.8.219.25458.8.219.255510
11158.8.220.0/2358.8.220.1 to 58.8.221.25458.8.221.255510
11258.8.222.0/2358.8.222.1 to 58.8.223.25458.8.223.255510
11358.8.224.0/2358.8.224.1 to 58.8.225.25458.8.225.255510
11458.8.226.0/2358.8.226.1 to 58.8.227.25458.8.227.255510
11558.8.228.0/2358.8.228.1 to 58.8.229.25458.8.229.255510
11658.8.230.0/2358.8.230.1 to 58.8.231.25458.8.231.255510
11758.8.232.0/2358.8.232.1 to 58.8.233.25458.8.233.255510
11858.8.234.0/2358.8.234.1 to 58.8.235.25458.8.235.255510
11958.8.236.0/2358.8.236.1 to 58.8.237.25458.8.237.255510
12058.8.238.0/2358.8.238.1 to 58.8.239.25458.8.239.255510
12158.8.240.0/2358.8.240.1 to 58.8.241.25458.8.241.255510
12258.8.242.0/2358.8.242.1 to 58.8.243.25458.8.243.255510
12358.8.244.0/2358.8.244.1 to 58.8.245.25458.8.245.255510
12458.8.246.0/2358.8.246.1 to 58.8.247.25458.8.247.255510
12558.8.248.0/2358.8.248.1 to 58.8.249.25458.8.249.255510
12658.8.250.0/2358.8.250.1 to 58.8.251.25458.8.251.255510
12758.8.252.0/2358.8.252.1 to 58.8.253.25458.8.253.255510
12858.8.254.0/2358.8.254.1 to 58.8.255.25458.8.255.255510
12958.9.0.0/2358.9.0.1 to 58.9.1.25458.9.1.255510
13058.9.2.0/2358.9.2.1 to 58.9.3.25458.9.3.255510
13158.9.4.0/2358.9.4.1 to 58.9.5.25458.9.5.255510
13258.9.6.0/2358.9.6.1 to 58.9.7.25458.9.7.255510
13358.9.8.0/2358.9.8.1 to 58.9.9.25458.9.9.255510
13458.9.10.0/2358.9.10.1 to 58.9.11.25458.9.11.255510
13558.9.12.0/2358.9.12.1 to 58.9.13.25458.9.13.255510
13658.9.14.0/2358.9.14.1 to 58.9.15.25458.9.15.255510
13758.9.16.0/2358.9.16.1 to 58.9.17.25458.9.17.255510
13858.9.18.0/2358.9.18.1 to 58.9.19.25458.9.19.255510
13958.9.20.0/2358.9.20.1 to 58.9.21.25458.9.21.255510
14058.9.22.0/2358.9.22.1 to 58.9.23.25458.9.23.255510
14158.9.24.0/2358.9.24.1 to 58.9.25.25458.9.25.255510
14258.9.26.0/2358.9.26.1 to 58.9.27.25458.9.27.255510
14358.9.28.0/2358.9.28.1 to 58.9.29.25458.9.29.255510
14458.9.30.0/2358.9.30.1 to 58.9.31.25458.9.31.255510
14558.9.32.0/2358.9.32.1 to 58.9.33.25458.9.33.255510
14658.9.34.0/2358.9.34.1 to 58.9.35.25458.9.35.255510
14758.9.36.0/2358.9.36.1 to 58.9.37.25458.9.37.255510
14858.9.38.0/2358.9.38.1 to 58.9.39.25458.9.39.255510
14958.9.40.0/2358.9.40.1 to 58.9.41.25458.9.41.255510
15058.9.42.0/2358.9.42.1 to 58.9.43.25458.9.43.255510
15158.9.44.0/2358.9.44.1 to 58.9.45.25458.9.45.255510
15258.9.46.0/2358.9.46.1 to 58.9.47.25458.9.47.255510
15358.9.48.0/2358.9.48.1 to 58.9.49.25458.9.49.255510
15458.9.50.0/2358.9.50.1 to 58.9.51.25458.9.51.255510
15558.9.52.0/2358.9.52.1 to 58.9.53.25458.9.53.255510
15658.9.54.0/2358.9.54.1 to 58.9.55.25458.9.55.255510
15758.9.56.0/2358.9.56.1 to 58.9.57.25458.9.57.255510
15858.9.58.0/2358.9.58.1 to 58.9.59.25458.9.59.255510
15958.9.60.0/2358.9.60.1 to 58.9.61.25458.9.61.255510
16058.9.62.0/2358.9.62.1 to 58.9.63.25458.9.63.255510
16158.9.64.0/2358.9.64.1 to 58.9.65.25458.9.65.255510
16258.9.66.0/2358.9.66.1 to 58.9.67.25458.9.67.255510
16358.9.68.0/2358.9.68.1 to 58.9.69.25458.9.69.255510
16458.9.70.0/2358.9.70.1 to 58.9.71.25458.9.71.255510
16558.9.72.0/2358.9.72.1 to 58.9.73.25458.9.73.255510
16658.9.74.0/2358.9.74.1 to 58.9.75.25458.9.75.255510
16758.9.76.0/2358.9.76.1 to 58.9.77.25458.9.77.255510
16858.9.78.0/2358.9.78.1 to 58.9.79.25458.9.79.255510
16958.9.80.0/2358.9.80.1 to 58.9.81.25458.9.81.255510
17058.9.82.0/2358.9.82.1 to 58.9.83.25458.9.83.255510
17158.9.84.0/2358.9.84.1 to 58.9.85.25458.9.85.255510
17258.9.86.0/2358.9.86.1 to 58.9.87.25458.9.87.255510
17358.9.88.0/2358.9.88.1 to 58.9.89.25458.9.89.255510
17458.9.90.0/2358.9.90.1 to 58.9.91.25458.9.91.255510
17558.9.92.0/2358.9.92.1 to 58.9.93.25458.9.93.255510
17658.9.94.0/2358.9.94.1 to 58.9.95.25458.9.95.255510
17758.9.96.0/2358.9.96.1 to 58.9.97.25458.9.97.255510
17858.9.98.0/2358.9.98.1 to 58.9.99.25458.9.99.255510
17958.9.100.0/2358.9.100.1 to 58.9.101.25458.9.101.255510
18058.9.102.0/2358.9.102.1 to 58.9.103.25458.9.103.255510
18158.9.104.0/2358.9.104.1 to 58.9.105.25458.9.105.255510
18258.9.106.0/2358.9.106.1 to 58.9.107.25458.9.107.255510
18358.9.108.0/2358.9.108.1 to 58.9.109.25458.9.109.255510
18458.9.110.0/2358.9.110.1 to 58.9.111.25458.9.111.255510
18558.9.112.0/2358.9.112.1 to 58.9.113.25458.9.113.255510
18658.9.114.0/2358.9.114.1 to 58.9.115.25458.9.115.255510
18758.9.116.0/2358.9.116.1 to 58.9.117.25458.9.117.255510
18858.9.118.0/2358.9.118.1 to 58.9.119.25458.9.119.255510
18958.9.120.0/2358.9.120.1 to 58.9.121.25458.9.121.255510
19058.9.122.0/2358.9.122.1 to 58.9.123.25458.9.123.255510
19158.9.124.0/2358.9.124.1 to 58.9.125.25458.9.125.255510
19258.9.126.0/2358.9.126.1 to 58.9.127.25458.9.127.255510
19358.9.128.0/2358.9.128.1 to 58.9.129.25458.9.129.255510
19458.9.130.0/2358.9.130.1 to 58.9.131.25458.9.131.255510
19558.9.132.0/2358.9.132.1 to 58.9.133.25458.9.133.255510
19658.9.134.0/2358.9.134.1 to 58.9.135.25458.9.135.255510
19758.9.136.0/2358.9.136.1 to 58.9.137.25458.9.137.255510
19858.9.138.0/2358.9.138.1 to 58.9.139.25458.9.139.255510
19958.9.140.0/2358.9.140.1 to 58.9.141.25458.9.141.255510
20058.9.142.0/2358.9.142.1 to 58.9.143.25458.9.143.255510
20158.9.144.0/2358.9.144.1 to 58.9.145.25458.9.145.255510
20258.9.146.0/2358.9.146.1 to 58.9.147.25458.9.147.255510
20358.9.148.0/2358.9.148.1 to 58.9.149.25458.9.149.255510
20458.9.150.0/2358.9.150.1 to 58.9.151.25458.9.151.255510
20558.9.152.0/2358.9.152.1 to 58.9.153.25458.9.153.255510
20658.9.154.0/2358.9.154.1 to 58.9.155.25458.9.155.255510
20758.9.156.0/2358.9.156.1 to 58.9.157.25458.9.157.255510
20858.9.158.0/2358.9.158.1 to 58.9.159.25458.9.159.255510
20958.9.160.0/2358.9.160.1 to 58.9.161.25458.9.161.255510
21058.9.162.0/2358.9.162.1 to 58.9.163.25458.9.163.255510
21158.9.164.0/2358.9.164.1 to 58.9.165.25458.9.165.255510
21258.9.166.0/2358.9.166.1 to 58.9.167.25458.9.167.255510
21358.9.168.0/2358.9.168.1 to 58.9.169.25458.9.169.255510
21458.9.170.0/2358.9.170.1 to 58.9.171.25458.9.171.255510
21558.9.172.0/2358.9.172.1 to 58.9.173.25458.9.173.255510
21658.9.174.0/2358.9.174.1 to 58.9.175.25458.9.175.255510
21758.9.176.0/2358.9.176.1 to 58.9.177.25458.9.177.255510
21858.9.178.0/2358.9.178.1 to 58.9.179.25458.9.179.255510
21958.9.180.0/2358.9.180.1 to 58.9.181.25458.9.181.255510
22058.9.182.0/2358.9.182.1 to 58.9.183.25458.9.183.255510
22158.9.184.0/2358.9.184.1 to 58.9.185.25458.9.185.255510
22258.9.186.0/2358.9.186.1 to 58.9.187.25458.9.187.255510
22358.9.188.0/2358.9.188.1 to 58.9.189.25458.9.189.255510
22458.9.190.0/2358.9.190.1 to 58.9.191.25458.9.191.255510
22558.9.192.0/2358.9.192.1 to 58.9.193.25458.9.193.255510
22658.9.194.0/2358.9.194.1 to 58.9.195.25458.9.195.255510
22758.9.196.0/2358.9.196.1 to 58.9.197.25458.9.197.255510
22858.9.198.0/2358.9.198.1 to 58.9.199.25458.9.199.255510
22958.9.200.0/2358.9.200.1 to 58.9.201.25458.9.201.255510
23058.9.202.0/2358.9.202.1 to 58.9.203.25458.9.203.255510
23158.9.204.0/2358.9.204.1 to 58.9.205.25458.9.205.255510
23258.9.206.0/2358.9.206.1 to 58.9.207.25458.9.207.255510
23358.9.208.0/2358.9.208.1 to 58.9.209.25458.9.209.255510
23458.9.210.0/2358.9.210.1 to 58.9.211.25458.9.211.255510
23558.9.212.0/2358.9.212.1 to 58.9.213.25458.9.213.255510
23658.9.214.0/2358.9.214.1 to 58.9.215.25458.9.215.255510
23758.9.216.0/2358.9.216.1 to 58.9.217.25458.9.217.255510
23858.9.218.0/2358.9.218.1 to 58.9.219.25458.9.219.255510
23958.9.220.0/2358.9.220.1 to 58.9.221.25458.9.221.255510
24058.9.222.0/2358.9.222.1 to 58.9.223.25458.9.223.255510
24158.9.224.0/2358.9.224.1 to 58.9.225.25458.9.225.255510
24258.9.226.0/2358.9.226.1 to 58.9.227.25458.9.227.255510
24358.9.228.0/2358.9.228.1 to 58.9.229.25458.9.229.255510
24458.9.230.0/2358.9.230.1 to 58.9.231.25458.9.231.255510
24558.9.232.0/2358.9.232.1 to 58.9.233.25458.9.233.255510
24658.9.234.0/2358.9.234.1 to 58.9.235.25458.9.235.255510
24758.9.236.0/2358.9.236.1 to 58.9.237.25458.9.237.255510
24858.9.238.0/2358.9.238.1 to 58.9.239.25458.9.239.255510
24958.9.240.0/2358.9.240.1 to 58.9.241.25458.9.241.255510
25058.9.242.0/2358.9.242.1 to 58.9.243.25458.9.243.255510
25158.9.244.0/2358.9.244.1 to 58.9.245.25458.9.245.255510
25258.9.246.0/2358.9.246.1 to 58.9.247.25458.9.247.255510
25358.9.248.0/2358.9.248.1 to 58.9.249.25458.9.249.255510
25458.9.250.0/2358.9.250.1 to 58.9.251.25458.9.251.255510
25558.9.252.0/2358.9.252.1 to 58.9.253.25458.9.253.255510
25658.9.254.0/2358.9.254.1 to 58.9.255.25458.9.255.255510

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.