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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.

Network93.0.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
93.0.0.0
Broadcast address
93.1.255.255
First usable
93.0.0.1
Last usable
93.1.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
A (default /8)
As numbers
Hex 5D000000 · Integer 1560281088 to 1560412159
Reverse DNS zones
0.93.in-addr.arpa
1.93.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011101.00000000.00000000.0000000093.0.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network01011101.00000000.00000000.0000000093.0.0.0
Broadcast01011101.00000001.11111111.1111111193.1.255.255
Split into smaller subnets/24
/16 (2)/17 (4)/18 (8)/19 (16)/20 (32)/21 (64)/22 (128)/23 (256)/24 (512)/25 (1,024)/26 (2,048)/27 (4,096)

93.0.0.0/15 makes 512 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
193.0.0.0/2493.0.0.1 to 93.0.0.25493.0.0.255254
293.0.1.0/2493.0.1.1 to 93.0.1.25493.0.1.255254
393.0.2.0/2493.0.2.1 to 93.0.2.25493.0.2.255254
493.0.3.0/2493.0.3.1 to 93.0.3.25493.0.3.255254
593.0.4.0/2493.0.4.1 to 93.0.4.25493.0.4.255254
693.0.5.0/2493.0.5.1 to 93.0.5.25493.0.5.255254
793.0.6.0/2493.0.6.1 to 93.0.6.25493.0.6.255254
893.0.7.0/2493.0.7.1 to 93.0.7.25493.0.7.255254
993.0.8.0/2493.0.8.1 to 93.0.8.25493.0.8.255254
1093.0.9.0/2493.0.9.1 to 93.0.9.25493.0.9.255254
1193.0.10.0/2493.0.10.1 to 93.0.10.25493.0.10.255254
1293.0.11.0/2493.0.11.1 to 93.0.11.25493.0.11.255254
1393.0.12.0/2493.0.12.1 to 93.0.12.25493.0.12.255254
1493.0.13.0/2493.0.13.1 to 93.0.13.25493.0.13.255254
1593.0.14.0/2493.0.14.1 to 93.0.14.25493.0.14.255254
1693.0.15.0/2493.0.15.1 to 93.0.15.25493.0.15.255254
1793.0.16.0/2493.0.16.1 to 93.0.16.25493.0.16.255254
1893.0.17.0/2493.0.17.1 to 93.0.17.25493.0.17.255254
1993.0.18.0/2493.0.18.1 to 93.0.18.25493.0.18.255254
2093.0.19.0/2493.0.19.1 to 93.0.19.25493.0.19.255254
2193.0.20.0/2493.0.20.1 to 93.0.20.25493.0.20.255254
2293.0.21.0/2493.0.21.1 to 93.0.21.25493.0.21.255254
2393.0.22.0/2493.0.22.1 to 93.0.22.25493.0.22.255254
2493.0.23.0/2493.0.23.1 to 93.0.23.25493.0.23.255254
2593.0.24.0/2493.0.24.1 to 93.0.24.25493.0.24.255254
2693.0.25.0/2493.0.25.1 to 93.0.25.25493.0.25.255254
2793.0.26.0/2493.0.26.1 to 93.0.26.25493.0.26.255254
2893.0.27.0/2493.0.27.1 to 93.0.27.25493.0.27.255254
2993.0.28.0/2493.0.28.1 to 93.0.28.25493.0.28.255254
3093.0.29.0/2493.0.29.1 to 93.0.29.25493.0.29.255254
3193.0.30.0/2493.0.30.1 to 93.0.30.25493.0.30.255254
3293.0.31.0/2493.0.31.1 to 93.0.31.25493.0.31.255254
3393.0.32.0/2493.0.32.1 to 93.0.32.25493.0.32.255254
3493.0.33.0/2493.0.33.1 to 93.0.33.25493.0.33.255254
3593.0.34.0/2493.0.34.1 to 93.0.34.25493.0.34.255254
3693.0.35.0/2493.0.35.1 to 93.0.35.25493.0.35.255254
3793.0.36.0/2493.0.36.1 to 93.0.36.25493.0.36.255254
3893.0.37.0/2493.0.37.1 to 93.0.37.25493.0.37.255254
3993.0.38.0/2493.0.38.1 to 93.0.38.25493.0.38.255254
4093.0.39.0/2493.0.39.1 to 93.0.39.25493.0.39.255254
4193.0.40.0/2493.0.40.1 to 93.0.40.25493.0.40.255254
4293.0.41.0/2493.0.41.1 to 93.0.41.25493.0.41.255254
4393.0.42.0/2493.0.42.1 to 93.0.42.25493.0.42.255254
4493.0.43.0/2493.0.43.1 to 93.0.43.25493.0.43.255254
4593.0.44.0/2493.0.44.1 to 93.0.44.25493.0.44.255254
4693.0.45.0/2493.0.45.1 to 93.0.45.25493.0.45.255254
4793.0.46.0/2493.0.46.1 to 93.0.46.25493.0.46.255254
4893.0.47.0/2493.0.47.1 to 93.0.47.25493.0.47.255254
4993.0.48.0/2493.0.48.1 to 93.0.48.25493.0.48.255254
5093.0.49.0/2493.0.49.1 to 93.0.49.25493.0.49.255254
5193.0.50.0/2493.0.50.1 to 93.0.50.25493.0.50.255254
5293.0.51.0/2493.0.51.1 to 93.0.51.25493.0.51.255254
5393.0.52.0/2493.0.52.1 to 93.0.52.25493.0.52.255254
5493.0.53.0/2493.0.53.1 to 93.0.53.25493.0.53.255254
5593.0.54.0/2493.0.54.1 to 93.0.54.25493.0.54.255254
5693.0.55.0/2493.0.55.1 to 93.0.55.25493.0.55.255254
5793.0.56.0/2493.0.56.1 to 93.0.56.25493.0.56.255254
5893.0.57.0/2493.0.57.1 to 93.0.57.25493.0.57.255254
5993.0.58.0/2493.0.58.1 to 93.0.58.25493.0.58.255254
6093.0.59.0/2493.0.59.1 to 93.0.59.25493.0.59.255254
6193.0.60.0/2493.0.60.1 to 93.0.60.25493.0.60.255254
6293.0.61.0/2493.0.61.1 to 93.0.61.25493.0.61.255254
6393.0.62.0/2493.0.62.1 to 93.0.62.25493.0.62.255254
6493.0.63.0/2493.0.63.1 to 93.0.63.25493.0.63.255254
6593.0.64.0/2493.0.64.1 to 93.0.64.25493.0.64.255254
6693.0.65.0/2493.0.65.1 to 93.0.65.25493.0.65.255254
6793.0.66.0/2493.0.66.1 to 93.0.66.25493.0.66.255254
6893.0.67.0/2493.0.67.1 to 93.0.67.25493.0.67.255254
6993.0.68.0/2493.0.68.1 to 93.0.68.25493.0.68.255254
7093.0.69.0/2493.0.69.1 to 93.0.69.25493.0.69.255254
7193.0.70.0/2493.0.70.1 to 93.0.70.25493.0.70.255254
7293.0.71.0/2493.0.71.1 to 93.0.71.25493.0.71.255254
7393.0.72.0/2493.0.72.1 to 93.0.72.25493.0.72.255254
7493.0.73.0/2493.0.73.1 to 93.0.73.25493.0.73.255254
7593.0.74.0/2493.0.74.1 to 93.0.74.25493.0.74.255254
7693.0.75.0/2493.0.75.1 to 93.0.75.25493.0.75.255254
7793.0.76.0/2493.0.76.1 to 93.0.76.25493.0.76.255254
7893.0.77.0/2493.0.77.1 to 93.0.77.25493.0.77.255254
7993.0.78.0/2493.0.78.1 to 93.0.78.25493.0.78.255254
8093.0.79.0/2493.0.79.1 to 93.0.79.25493.0.79.255254
8193.0.80.0/2493.0.80.1 to 93.0.80.25493.0.80.255254
8293.0.81.0/2493.0.81.1 to 93.0.81.25493.0.81.255254
8393.0.82.0/2493.0.82.1 to 93.0.82.25493.0.82.255254
8493.0.83.0/2493.0.83.1 to 93.0.83.25493.0.83.255254
8593.0.84.0/2493.0.84.1 to 93.0.84.25493.0.84.255254
8693.0.85.0/2493.0.85.1 to 93.0.85.25493.0.85.255254
8793.0.86.0/2493.0.86.1 to 93.0.86.25493.0.86.255254
8893.0.87.0/2493.0.87.1 to 93.0.87.25493.0.87.255254
8993.0.88.0/2493.0.88.1 to 93.0.88.25493.0.88.255254
9093.0.89.0/2493.0.89.1 to 93.0.89.25493.0.89.255254
9193.0.90.0/2493.0.90.1 to 93.0.90.25493.0.90.255254
9293.0.91.0/2493.0.91.1 to 93.0.91.25493.0.91.255254
9393.0.92.0/2493.0.92.1 to 93.0.92.25493.0.92.255254
9493.0.93.0/2493.0.93.1 to 93.0.93.25493.0.93.255254
9593.0.94.0/2493.0.94.1 to 93.0.94.25493.0.94.255254
9693.0.95.0/2493.0.95.1 to 93.0.95.25493.0.95.255254
9793.0.96.0/2493.0.96.1 to 93.0.96.25493.0.96.255254
9893.0.97.0/2493.0.97.1 to 93.0.97.25493.0.97.255254
9993.0.98.0/2493.0.98.1 to 93.0.98.25493.0.98.255254
10093.0.99.0/2493.0.99.1 to 93.0.99.25493.0.99.255254
10193.0.100.0/2493.0.100.1 to 93.0.100.25493.0.100.255254
10293.0.101.0/2493.0.101.1 to 93.0.101.25493.0.101.255254
10393.0.102.0/2493.0.102.1 to 93.0.102.25493.0.102.255254
10493.0.103.0/2493.0.103.1 to 93.0.103.25493.0.103.255254
10593.0.104.0/2493.0.104.1 to 93.0.104.25493.0.104.255254
10693.0.105.0/2493.0.105.1 to 93.0.105.25493.0.105.255254
10793.0.106.0/2493.0.106.1 to 93.0.106.25493.0.106.255254
10893.0.107.0/2493.0.107.1 to 93.0.107.25493.0.107.255254
10993.0.108.0/2493.0.108.1 to 93.0.108.25493.0.108.255254
11093.0.109.0/2493.0.109.1 to 93.0.109.25493.0.109.255254
11193.0.110.0/2493.0.110.1 to 93.0.110.25493.0.110.255254
11293.0.111.0/2493.0.111.1 to 93.0.111.25493.0.111.255254
11393.0.112.0/2493.0.112.1 to 93.0.112.25493.0.112.255254
11493.0.113.0/2493.0.113.1 to 93.0.113.25493.0.113.255254
11593.0.114.0/2493.0.114.1 to 93.0.114.25493.0.114.255254
11693.0.115.0/2493.0.115.1 to 93.0.115.25493.0.115.255254
11793.0.116.0/2493.0.116.1 to 93.0.116.25493.0.116.255254
11893.0.117.0/2493.0.117.1 to 93.0.117.25493.0.117.255254
11993.0.118.0/2493.0.118.1 to 93.0.118.25493.0.118.255254
12093.0.119.0/2493.0.119.1 to 93.0.119.25493.0.119.255254
12193.0.120.0/2493.0.120.1 to 93.0.120.25493.0.120.255254
12293.0.121.0/2493.0.121.1 to 93.0.121.25493.0.121.255254
12393.0.122.0/2493.0.122.1 to 93.0.122.25493.0.122.255254
12493.0.123.0/2493.0.123.1 to 93.0.123.25493.0.123.255254
12593.0.124.0/2493.0.124.1 to 93.0.124.25493.0.124.255254
12693.0.125.0/2493.0.125.1 to 93.0.125.25493.0.125.255254
12793.0.126.0/2493.0.126.1 to 93.0.126.25493.0.126.255254
12893.0.127.0/2493.0.127.1 to 93.0.127.25493.0.127.255254
12993.0.128.0/2493.0.128.1 to 93.0.128.25493.0.128.255254
13093.0.129.0/2493.0.129.1 to 93.0.129.25493.0.129.255254
13193.0.130.0/2493.0.130.1 to 93.0.130.25493.0.130.255254
13293.0.131.0/2493.0.131.1 to 93.0.131.25493.0.131.255254
13393.0.132.0/2493.0.132.1 to 93.0.132.25493.0.132.255254
13493.0.133.0/2493.0.133.1 to 93.0.133.25493.0.133.255254
13593.0.134.0/2493.0.134.1 to 93.0.134.25493.0.134.255254
13693.0.135.0/2493.0.135.1 to 93.0.135.25493.0.135.255254
13793.0.136.0/2493.0.136.1 to 93.0.136.25493.0.136.255254
13893.0.137.0/2493.0.137.1 to 93.0.137.25493.0.137.255254
13993.0.138.0/2493.0.138.1 to 93.0.138.25493.0.138.255254
14093.0.139.0/2493.0.139.1 to 93.0.139.25493.0.139.255254
14193.0.140.0/2493.0.140.1 to 93.0.140.25493.0.140.255254
14293.0.141.0/2493.0.141.1 to 93.0.141.25493.0.141.255254
14393.0.142.0/2493.0.142.1 to 93.0.142.25493.0.142.255254
14493.0.143.0/2493.0.143.1 to 93.0.143.25493.0.143.255254
14593.0.144.0/2493.0.144.1 to 93.0.144.25493.0.144.255254
14693.0.145.0/2493.0.145.1 to 93.0.145.25493.0.145.255254
14793.0.146.0/2493.0.146.1 to 93.0.146.25493.0.146.255254
14893.0.147.0/2493.0.147.1 to 93.0.147.25493.0.147.255254
14993.0.148.0/2493.0.148.1 to 93.0.148.25493.0.148.255254
15093.0.149.0/2493.0.149.1 to 93.0.149.25493.0.149.255254
15193.0.150.0/2493.0.150.1 to 93.0.150.25493.0.150.255254
15293.0.151.0/2493.0.151.1 to 93.0.151.25493.0.151.255254
15393.0.152.0/2493.0.152.1 to 93.0.152.25493.0.152.255254
15493.0.153.0/2493.0.153.1 to 93.0.153.25493.0.153.255254
15593.0.154.0/2493.0.154.1 to 93.0.154.25493.0.154.255254
15693.0.155.0/2493.0.155.1 to 93.0.155.25493.0.155.255254
15793.0.156.0/2493.0.156.1 to 93.0.156.25493.0.156.255254
15893.0.157.0/2493.0.157.1 to 93.0.157.25493.0.157.255254
15993.0.158.0/2493.0.158.1 to 93.0.158.25493.0.158.255254
16093.0.159.0/2493.0.159.1 to 93.0.159.25493.0.159.255254
16193.0.160.0/2493.0.160.1 to 93.0.160.25493.0.160.255254
16293.0.161.0/2493.0.161.1 to 93.0.161.25493.0.161.255254
16393.0.162.0/2493.0.162.1 to 93.0.162.25493.0.162.255254
16493.0.163.0/2493.0.163.1 to 93.0.163.25493.0.163.255254
16593.0.164.0/2493.0.164.1 to 93.0.164.25493.0.164.255254
16693.0.165.0/2493.0.165.1 to 93.0.165.25493.0.165.255254
16793.0.166.0/2493.0.166.1 to 93.0.166.25493.0.166.255254
16893.0.167.0/2493.0.167.1 to 93.0.167.25493.0.167.255254
16993.0.168.0/2493.0.168.1 to 93.0.168.25493.0.168.255254
17093.0.169.0/2493.0.169.1 to 93.0.169.25493.0.169.255254
17193.0.170.0/2493.0.170.1 to 93.0.170.25493.0.170.255254
17293.0.171.0/2493.0.171.1 to 93.0.171.25493.0.171.255254
17393.0.172.0/2493.0.172.1 to 93.0.172.25493.0.172.255254
17493.0.173.0/2493.0.173.1 to 93.0.173.25493.0.173.255254
17593.0.174.0/2493.0.174.1 to 93.0.174.25493.0.174.255254
17693.0.175.0/2493.0.175.1 to 93.0.175.25493.0.175.255254
17793.0.176.0/2493.0.176.1 to 93.0.176.25493.0.176.255254
17893.0.177.0/2493.0.177.1 to 93.0.177.25493.0.177.255254
17993.0.178.0/2493.0.178.1 to 93.0.178.25493.0.178.255254
18093.0.179.0/2493.0.179.1 to 93.0.179.25493.0.179.255254
18193.0.180.0/2493.0.180.1 to 93.0.180.25493.0.180.255254
18293.0.181.0/2493.0.181.1 to 93.0.181.25493.0.181.255254
18393.0.182.0/2493.0.182.1 to 93.0.182.25493.0.182.255254
18493.0.183.0/2493.0.183.1 to 93.0.183.25493.0.183.255254
18593.0.184.0/2493.0.184.1 to 93.0.184.25493.0.184.255254
18693.0.185.0/2493.0.185.1 to 93.0.185.25493.0.185.255254
18793.0.186.0/2493.0.186.1 to 93.0.186.25493.0.186.255254
18893.0.187.0/2493.0.187.1 to 93.0.187.25493.0.187.255254
18993.0.188.0/2493.0.188.1 to 93.0.188.25493.0.188.255254
19093.0.189.0/2493.0.189.1 to 93.0.189.25493.0.189.255254
19193.0.190.0/2493.0.190.1 to 93.0.190.25493.0.190.255254
19293.0.191.0/2493.0.191.1 to 93.0.191.25493.0.191.255254
19393.0.192.0/2493.0.192.1 to 93.0.192.25493.0.192.255254
19493.0.193.0/2493.0.193.1 to 93.0.193.25493.0.193.255254
19593.0.194.0/2493.0.194.1 to 93.0.194.25493.0.194.255254
19693.0.195.0/2493.0.195.1 to 93.0.195.25493.0.195.255254
19793.0.196.0/2493.0.196.1 to 93.0.196.25493.0.196.255254
19893.0.197.0/2493.0.197.1 to 93.0.197.25493.0.197.255254
19993.0.198.0/2493.0.198.1 to 93.0.198.25493.0.198.255254
20093.0.199.0/2493.0.199.1 to 93.0.199.25493.0.199.255254
20193.0.200.0/2493.0.200.1 to 93.0.200.25493.0.200.255254
20293.0.201.0/2493.0.201.1 to 93.0.201.25493.0.201.255254
20393.0.202.0/2493.0.202.1 to 93.0.202.25493.0.202.255254
20493.0.203.0/2493.0.203.1 to 93.0.203.25493.0.203.255254
20593.0.204.0/2493.0.204.1 to 93.0.204.25493.0.204.255254
20693.0.205.0/2493.0.205.1 to 93.0.205.25493.0.205.255254
20793.0.206.0/2493.0.206.1 to 93.0.206.25493.0.206.255254
20893.0.207.0/2493.0.207.1 to 93.0.207.25493.0.207.255254
20993.0.208.0/2493.0.208.1 to 93.0.208.25493.0.208.255254
21093.0.209.0/2493.0.209.1 to 93.0.209.25493.0.209.255254
21193.0.210.0/2493.0.210.1 to 93.0.210.25493.0.210.255254
21293.0.211.0/2493.0.211.1 to 93.0.211.25493.0.211.255254
21393.0.212.0/2493.0.212.1 to 93.0.212.25493.0.212.255254
21493.0.213.0/2493.0.213.1 to 93.0.213.25493.0.213.255254
21593.0.214.0/2493.0.214.1 to 93.0.214.25493.0.214.255254
21693.0.215.0/2493.0.215.1 to 93.0.215.25493.0.215.255254
21793.0.216.0/2493.0.216.1 to 93.0.216.25493.0.216.255254
21893.0.217.0/2493.0.217.1 to 93.0.217.25493.0.217.255254
21993.0.218.0/2493.0.218.1 to 93.0.218.25493.0.218.255254
22093.0.219.0/2493.0.219.1 to 93.0.219.25493.0.219.255254
22193.0.220.0/2493.0.220.1 to 93.0.220.25493.0.220.255254
22293.0.221.0/2493.0.221.1 to 93.0.221.25493.0.221.255254
22393.0.222.0/2493.0.222.1 to 93.0.222.25493.0.222.255254
22493.0.223.0/2493.0.223.1 to 93.0.223.25493.0.223.255254
22593.0.224.0/2493.0.224.1 to 93.0.224.25493.0.224.255254
22693.0.225.0/2493.0.225.1 to 93.0.225.25493.0.225.255254
22793.0.226.0/2493.0.226.1 to 93.0.226.25493.0.226.255254
22893.0.227.0/2493.0.227.1 to 93.0.227.25493.0.227.255254
22993.0.228.0/2493.0.228.1 to 93.0.228.25493.0.228.255254
23093.0.229.0/2493.0.229.1 to 93.0.229.25493.0.229.255254
23193.0.230.0/2493.0.230.1 to 93.0.230.25493.0.230.255254
23293.0.231.0/2493.0.231.1 to 93.0.231.25493.0.231.255254
23393.0.232.0/2493.0.232.1 to 93.0.232.25493.0.232.255254
23493.0.233.0/2493.0.233.1 to 93.0.233.25493.0.233.255254
23593.0.234.0/2493.0.234.1 to 93.0.234.25493.0.234.255254
23693.0.235.0/2493.0.235.1 to 93.0.235.25493.0.235.255254
23793.0.236.0/2493.0.236.1 to 93.0.236.25493.0.236.255254
23893.0.237.0/2493.0.237.1 to 93.0.237.25493.0.237.255254
23993.0.238.0/2493.0.238.1 to 93.0.238.25493.0.238.255254
24093.0.239.0/2493.0.239.1 to 93.0.239.25493.0.239.255254
24193.0.240.0/2493.0.240.1 to 93.0.240.25493.0.240.255254
24293.0.241.0/2493.0.241.1 to 93.0.241.25493.0.241.255254
24393.0.242.0/2493.0.242.1 to 93.0.242.25493.0.242.255254
24493.0.243.0/2493.0.243.1 to 93.0.243.25493.0.243.255254
24593.0.244.0/2493.0.244.1 to 93.0.244.25493.0.244.255254
24693.0.245.0/2493.0.245.1 to 93.0.245.25493.0.245.255254
24793.0.246.0/2493.0.246.1 to 93.0.246.25493.0.246.255254
24893.0.247.0/2493.0.247.1 to 93.0.247.25493.0.247.255254
24993.0.248.0/2493.0.248.1 to 93.0.248.25493.0.248.255254
25093.0.249.0/2493.0.249.1 to 93.0.249.25493.0.249.255254
25193.0.250.0/2493.0.250.1 to 93.0.250.25493.0.250.255254
25293.0.251.0/2493.0.251.1 to 93.0.251.25493.0.251.255254
25393.0.252.0/2493.0.252.1 to 93.0.252.25493.0.252.255254
25493.0.253.0/2493.0.253.1 to 93.0.253.25493.0.253.255254
25593.0.254.0/2493.0.254.1 to 93.0.254.25493.0.254.255254
25693.0.255.0/2493.0.255.1 to 93.0.255.25493.0.255.255254

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.