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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.

Network93.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
93.0.0.0
Broadcast address
93.127.255.255
First usable
93.0.0.1
Last usable
93.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 5D000000 · Integer 1560281088 to 1568669695
Reverse DNS zones
0.93.in-addr.arpa
1.93.in-addr.arpa
2.93.in-addr.arpa
3.93.in-addr.arpa
4.93.in-addr.arpa
5.93.in-addr.arpa
6.93.in-addr.arpa
7.93.in-addr.arpa
8.93.in-addr.arpa
9.93.in-addr.arpa
10.93.in-addr.arpa
11.93.in-addr.arpa
12.93.in-addr.arpa
13.93.in-addr.arpa
14.93.in-addr.arpa
15.93.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011101.00000000.00000000.0000000093.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01011101.00000000.00000000.0000000093.0.0.0
Broadcast01011101.01111111.11111111.1111111193.127.255.255
Split into smaller subnets/21
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

93.0.0.0/9 makes 4,096 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
193.0.0.0/2193.0.0.1 to 93.0.7.25493.0.7.2552,046
293.0.8.0/2193.0.8.1 to 93.0.15.25493.0.15.2552,046
393.0.16.0/2193.0.16.1 to 93.0.23.25493.0.23.2552,046
493.0.24.0/2193.0.24.1 to 93.0.31.25493.0.31.2552,046
593.0.32.0/2193.0.32.1 to 93.0.39.25493.0.39.2552,046
693.0.40.0/2193.0.40.1 to 93.0.47.25493.0.47.2552,046
793.0.48.0/2193.0.48.1 to 93.0.55.25493.0.55.2552,046
893.0.56.0/2193.0.56.1 to 93.0.63.25493.0.63.2552,046
993.0.64.0/2193.0.64.1 to 93.0.71.25493.0.71.2552,046
1093.0.72.0/2193.0.72.1 to 93.0.79.25493.0.79.2552,046
1193.0.80.0/2193.0.80.1 to 93.0.87.25493.0.87.2552,046
1293.0.88.0/2193.0.88.1 to 93.0.95.25493.0.95.2552,046
1393.0.96.0/2193.0.96.1 to 93.0.103.25493.0.103.2552,046
1493.0.104.0/2193.0.104.1 to 93.0.111.25493.0.111.2552,046
1593.0.112.0/2193.0.112.1 to 93.0.119.25493.0.119.2552,046
1693.0.120.0/2193.0.120.1 to 93.0.127.25493.0.127.2552,046
1793.0.128.0/2193.0.128.1 to 93.0.135.25493.0.135.2552,046
1893.0.136.0/2193.0.136.1 to 93.0.143.25493.0.143.2552,046
1993.0.144.0/2193.0.144.1 to 93.0.151.25493.0.151.2552,046
2093.0.152.0/2193.0.152.1 to 93.0.159.25493.0.159.2552,046
2193.0.160.0/2193.0.160.1 to 93.0.167.25493.0.167.2552,046
2293.0.168.0/2193.0.168.1 to 93.0.175.25493.0.175.2552,046
2393.0.176.0/2193.0.176.1 to 93.0.183.25493.0.183.2552,046
2493.0.184.0/2193.0.184.1 to 93.0.191.25493.0.191.2552,046
2593.0.192.0/2193.0.192.1 to 93.0.199.25493.0.199.2552,046
2693.0.200.0/2193.0.200.1 to 93.0.207.25493.0.207.2552,046
2793.0.208.0/2193.0.208.1 to 93.0.215.25493.0.215.2552,046
2893.0.216.0/2193.0.216.1 to 93.0.223.25493.0.223.2552,046
2993.0.224.0/2193.0.224.1 to 93.0.231.25493.0.231.2552,046
3093.0.232.0/2193.0.232.1 to 93.0.239.25493.0.239.2552,046
3193.0.240.0/2193.0.240.1 to 93.0.247.25493.0.247.2552,046
3293.0.248.0/2193.0.248.1 to 93.0.255.25493.0.255.2552,046
3393.1.0.0/2193.1.0.1 to 93.1.7.25493.1.7.2552,046
3493.1.8.0/2193.1.8.1 to 93.1.15.25493.1.15.2552,046
3593.1.16.0/2193.1.16.1 to 93.1.23.25493.1.23.2552,046
3693.1.24.0/2193.1.24.1 to 93.1.31.25493.1.31.2552,046
3793.1.32.0/2193.1.32.1 to 93.1.39.25493.1.39.2552,046
3893.1.40.0/2193.1.40.1 to 93.1.47.25493.1.47.2552,046
3993.1.48.0/2193.1.48.1 to 93.1.55.25493.1.55.2552,046
4093.1.56.0/2193.1.56.1 to 93.1.63.25493.1.63.2552,046
4193.1.64.0/2193.1.64.1 to 93.1.71.25493.1.71.2552,046
4293.1.72.0/2193.1.72.1 to 93.1.79.25493.1.79.2552,046
4393.1.80.0/2193.1.80.1 to 93.1.87.25493.1.87.2552,046
4493.1.88.0/2193.1.88.1 to 93.1.95.25493.1.95.2552,046
4593.1.96.0/2193.1.96.1 to 93.1.103.25493.1.103.2552,046
4693.1.104.0/2193.1.104.1 to 93.1.111.25493.1.111.2552,046
4793.1.112.0/2193.1.112.1 to 93.1.119.25493.1.119.2552,046
4893.1.120.0/2193.1.120.1 to 93.1.127.25493.1.127.2552,046
4993.1.128.0/2193.1.128.1 to 93.1.135.25493.1.135.2552,046
5093.1.136.0/2193.1.136.1 to 93.1.143.25493.1.143.2552,046
5193.1.144.0/2193.1.144.1 to 93.1.151.25493.1.151.2552,046
5293.1.152.0/2193.1.152.1 to 93.1.159.25493.1.159.2552,046
5393.1.160.0/2193.1.160.1 to 93.1.167.25493.1.167.2552,046
5493.1.168.0/2193.1.168.1 to 93.1.175.25493.1.175.2552,046
5593.1.176.0/2193.1.176.1 to 93.1.183.25493.1.183.2552,046
5693.1.184.0/2193.1.184.1 to 93.1.191.25493.1.191.2552,046
5793.1.192.0/2193.1.192.1 to 93.1.199.25493.1.199.2552,046
5893.1.200.0/2193.1.200.1 to 93.1.207.25493.1.207.2552,046
5993.1.208.0/2193.1.208.1 to 93.1.215.25493.1.215.2552,046
6093.1.216.0/2193.1.216.1 to 93.1.223.25493.1.223.2552,046
6193.1.224.0/2193.1.224.1 to 93.1.231.25493.1.231.2552,046
6293.1.232.0/2193.1.232.1 to 93.1.239.25493.1.239.2552,046
6393.1.240.0/2193.1.240.1 to 93.1.247.25493.1.247.2552,046
6493.1.248.0/2193.1.248.1 to 93.1.255.25493.1.255.2552,046
6593.2.0.0/2193.2.0.1 to 93.2.7.25493.2.7.2552,046
6693.2.8.0/2193.2.8.1 to 93.2.15.25493.2.15.2552,046
6793.2.16.0/2193.2.16.1 to 93.2.23.25493.2.23.2552,046
6893.2.24.0/2193.2.24.1 to 93.2.31.25493.2.31.2552,046
6993.2.32.0/2193.2.32.1 to 93.2.39.25493.2.39.2552,046
7093.2.40.0/2193.2.40.1 to 93.2.47.25493.2.47.2552,046
7193.2.48.0/2193.2.48.1 to 93.2.55.25493.2.55.2552,046
7293.2.56.0/2193.2.56.1 to 93.2.63.25493.2.63.2552,046
7393.2.64.0/2193.2.64.1 to 93.2.71.25493.2.71.2552,046
7493.2.72.0/2193.2.72.1 to 93.2.79.25493.2.79.2552,046
7593.2.80.0/2193.2.80.1 to 93.2.87.25493.2.87.2552,046
7693.2.88.0/2193.2.88.1 to 93.2.95.25493.2.95.2552,046
7793.2.96.0/2193.2.96.1 to 93.2.103.25493.2.103.2552,046
7893.2.104.0/2193.2.104.1 to 93.2.111.25493.2.111.2552,046
7993.2.112.0/2193.2.112.1 to 93.2.119.25493.2.119.2552,046
8093.2.120.0/2193.2.120.1 to 93.2.127.25493.2.127.2552,046
8193.2.128.0/2193.2.128.1 to 93.2.135.25493.2.135.2552,046
8293.2.136.0/2193.2.136.1 to 93.2.143.25493.2.143.2552,046
8393.2.144.0/2193.2.144.1 to 93.2.151.25493.2.151.2552,046
8493.2.152.0/2193.2.152.1 to 93.2.159.25493.2.159.2552,046
8593.2.160.0/2193.2.160.1 to 93.2.167.25493.2.167.2552,046
8693.2.168.0/2193.2.168.1 to 93.2.175.25493.2.175.2552,046
8793.2.176.0/2193.2.176.1 to 93.2.183.25493.2.183.2552,046
8893.2.184.0/2193.2.184.1 to 93.2.191.25493.2.191.2552,046
8993.2.192.0/2193.2.192.1 to 93.2.199.25493.2.199.2552,046
9093.2.200.0/2193.2.200.1 to 93.2.207.25493.2.207.2552,046
9193.2.208.0/2193.2.208.1 to 93.2.215.25493.2.215.2552,046
9293.2.216.0/2193.2.216.1 to 93.2.223.25493.2.223.2552,046
9393.2.224.0/2193.2.224.1 to 93.2.231.25493.2.231.2552,046
9493.2.232.0/2193.2.232.1 to 93.2.239.25493.2.239.2552,046
9593.2.240.0/2193.2.240.1 to 93.2.247.25493.2.247.2552,046
9693.2.248.0/2193.2.248.1 to 93.2.255.25493.2.255.2552,046
9793.3.0.0/2193.3.0.1 to 93.3.7.25493.3.7.2552,046
9893.3.8.0/2193.3.8.1 to 93.3.15.25493.3.15.2552,046
9993.3.16.0/2193.3.16.1 to 93.3.23.25493.3.23.2552,046
10093.3.24.0/2193.3.24.1 to 93.3.31.25493.3.31.2552,046
10193.3.32.0/2193.3.32.1 to 93.3.39.25493.3.39.2552,046
10293.3.40.0/2193.3.40.1 to 93.3.47.25493.3.47.2552,046
10393.3.48.0/2193.3.48.1 to 93.3.55.25493.3.55.2552,046
10493.3.56.0/2193.3.56.1 to 93.3.63.25493.3.63.2552,046
10593.3.64.0/2193.3.64.1 to 93.3.71.25493.3.71.2552,046
10693.3.72.0/2193.3.72.1 to 93.3.79.25493.3.79.2552,046
10793.3.80.0/2193.3.80.1 to 93.3.87.25493.3.87.2552,046
10893.3.88.0/2193.3.88.1 to 93.3.95.25493.3.95.2552,046
10993.3.96.0/2193.3.96.1 to 93.3.103.25493.3.103.2552,046
11093.3.104.0/2193.3.104.1 to 93.3.111.25493.3.111.2552,046
11193.3.112.0/2193.3.112.1 to 93.3.119.25493.3.119.2552,046
11293.3.120.0/2193.3.120.1 to 93.3.127.25493.3.127.2552,046
11393.3.128.0/2193.3.128.1 to 93.3.135.25493.3.135.2552,046
11493.3.136.0/2193.3.136.1 to 93.3.143.25493.3.143.2552,046
11593.3.144.0/2193.3.144.1 to 93.3.151.25493.3.151.2552,046
11693.3.152.0/2193.3.152.1 to 93.3.159.25493.3.159.2552,046
11793.3.160.0/2193.3.160.1 to 93.3.167.25493.3.167.2552,046
11893.3.168.0/2193.3.168.1 to 93.3.175.25493.3.175.2552,046
11993.3.176.0/2193.3.176.1 to 93.3.183.25493.3.183.2552,046
12093.3.184.0/2193.3.184.1 to 93.3.191.25493.3.191.2552,046
12193.3.192.0/2193.3.192.1 to 93.3.199.25493.3.199.2552,046
12293.3.200.0/2193.3.200.1 to 93.3.207.25493.3.207.2552,046
12393.3.208.0/2193.3.208.1 to 93.3.215.25493.3.215.2552,046
12493.3.216.0/2193.3.216.1 to 93.3.223.25493.3.223.2552,046
12593.3.224.0/2193.3.224.1 to 93.3.231.25493.3.231.2552,046
12693.3.232.0/2193.3.232.1 to 93.3.239.25493.3.239.2552,046
12793.3.240.0/2193.3.240.1 to 93.3.247.25493.3.247.2552,046
12893.3.248.0/2193.3.248.1 to 93.3.255.25493.3.255.2552,046
12993.4.0.0/2193.4.0.1 to 93.4.7.25493.4.7.2552,046
13093.4.8.0/2193.4.8.1 to 93.4.15.25493.4.15.2552,046
13193.4.16.0/2193.4.16.1 to 93.4.23.25493.4.23.2552,046
13293.4.24.0/2193.4.24.1 to 93.4.31.25493.4.31.2552,046
13393.4.32.0/2193.4.32.1 to 93.4.39.25493.4.39.2552,046
13493.4.40.0/2193.4.40.1 to 93.4.47.25493.4.47.2552,046
13593.4.48.0/2193.4.48.1 to 93.4.55.25493.4.55.2552,046
13693.4.56.0/2193.4.56.1 to 93.4.63.25493.4.63.2552,046
13793.4.64.0/2193.4.64.1 to 93.4.71.25493.4.71.2552,046
13893.4.72.0/2193.4.72.1 to 93.4.79.25493.4.79.2552,046
13993.4.80.0/2193.4.80.1 to 93.4.87.25493.4.87.2552,046
14093.4.88.0/2193.4.88.1 to 93.4.95.25493.4.95.2552,046
14193.4.96.0/2193.4.96.1 to 93.4.103.25493.4.103.2552,046
14293.4.104.0/2193.4.104.1 to 93.4.111.25493.4.111.2552,046
14393.4.112.0/2193.4.112.1 to 93.4.119.25493.4.119.2552,046
14493.4.120.0/2193.4.120.1 to 93.4.127.25493.4.127.2552,046
14593.4.128.0/2193.4.128.1 to 93.4.135.25493.4.135.2552,046
14693.4.136.0/2193.4.136.1 to 93.4.143.25493.4.143.2552,046
14793.4.144.0/2193.4.144.1 to 93.4.151.25493.4.151.2552,046
14893.4.152.0/2193.4.152.1 to 93.4.159.25493.4.159.2552,046
14993.4.160.0/2193.4.160.1 to 93.4.167.25493.4.167.2552,046
15093.4.168.0/2193.4.168.1 to 93.4.175.25493.4.175.2552,046
15193.4.176.0/2193.4.176.1 to 93.4.183.25493.4.183.2552,046
15293.4.184.0/2193.4.184.1 to 93.4.191.25493.4.191.2552,046
15393.4.192.0/2193.4.192.1 to 93.4.199.25493.4.199.2552,046
15493.4.200.0/2193.4.200.1 to 93.4.207.25493.4.207.2552,046
15593.4.208.0/2193.4.208.1 to 93.4.215.25493.4.215.2552,046
15693.4.216.0/2193.4.216.1 to 93.4.223.25493.4.223.2552,046
15793.4.224.0/2193.4.224.1 to 93.4.231.25493.4.231.2552,046
15893.4.232.0/2193.4.232.1 to 93.4.239.25493.4.239.2552,046
15993.4.240.0/2193.4.240.1 to 93.4.247.25493.4.247.2552,046
16093.4.248.0/2193.4.248.1 to 93.4.255.25493.4.255.2552,046
16193.5.0.0/2193.5.0.1 to 93.5.7.25493.5.7.2552,046
16293.5.8.0/2193.5.8.1 to 93.5.15.25493.5.15.2552,046
16393.5.16.0/2193.5.16.1 to 93.5.23.25493.5.23.2552,046
16493.5.24.0/2193.5.24.1 to 93.5.31.25493.5.31.2552,046
16593.5.32.0/2193.5.32.1 to 93.5.39.25493.5.39.2552,046
16693.5.40.0/2193.5.40.1 to 93.5.47.25493.5.47.2552,046
16793.5.48.0/2193.5.48.1 to 93.5.55.25493.5.55.2552,046
16893.5.56.0/2193.5.56.1 to 93.5.63.25493.5.63.2552,046
16993.5.64.0/2193.5.64.1 to 93.5.71.25493.5.71.2552,046
17093.5.72.0/2193.5.72.1 to 93.5.79.25493.5.79.2552,046
17193.5.80.0/2193.5.80.1 to 93.5.87.25493.5.87.2552,046
17293.5.88.0/2193.5.88.1 to 93.5.95.25493.5.95.2552,046
17393.5.96.0/2193.5.96.1 to 93.5.103.25493.5.103.2552,046
17493.5.104.0/2193.5.104.1 to 93.5.111.25493.5.111.2552,046
17593.5.112.0/2193.5.112.1 to 93.5.119.25493.5.119.2552,046
17693.5.120.0/2193.5.120.1 to 93.5.127.25493.5.127.2552,046
17793.5.128.0/2193.5.128.1 to 93.5.135.25493.5.135.2552,046
17893.5.136.0/2193.5.136.1 to 93.5.143.25493.5.143.2552,046
17993.5.144.0/2193.5.144.1 to 93.5.151.25493.5.151.2552,046
18093.5.152.0/2193.5.152.1 to 93.5.159.25493.5.159.2552,046
18193.5.160.0/2193.5.160.1 to 93.5.167.25493.5.167.2552,046
18293.5.168.0/2193.5.168.1 to 93.5.175.25493.5.175.2552,046
18393.5.176.0/2193.5.176.1 to 93.5.183.25493.5.183.2552,046
18493.5.184.0/2193.5.184.1 to 93.5.191.25493.5.191.2552,046
18593.5.192.0/2193.5.192.1 to 93.5.199.25493.5.199.2552,046
18693.5.200.0/2193.5.200.1 to 93.5.207.25493.5.207.2552,046
18793.5.208.0/2193.5.208.1 to 93.5.215.25493.5.215.2552,046
18893.5.216.0/2193.5.216.1 to 93.5.223.25493.5.223.2552,046
18993.5.224.0/2193.5.224.1 to 93.5.231.25493.5.231.2552,046
19093.5.232.0/2193.5.232.1 to 93.5.239.25493.5.239.2552,046
19193.5.240.0/2193.5.240.1 to 93.5.247.25493.5.247.2552,046
19293.5.248.0/2193.5.248.1 to 93.5.255.25493.5.255.2552,046
19393.6.0.0/2193.6.0.1 to 93.6.7.25493.6.7.2552,046
19493.6.8.0/2193.6.8.1 to 93.6.15.25493.6.15.2552,046
19593.6.16.0/2193.6.16.1 to 93.6.23.25493.6.23.2552,046
19693.6.24.0/2193.6.24.1 to 93.6.31.25493.6.31.2552,046
19793.6.32.0/2193.6.32.1 to 93.6.39.25493.6.39.2552,046
19893.6.40.0/2193.6.40.1 to 93.6.47.25493.6.47.2552,046
19993.6.48.0/2193.6.48.1 to 93.6.55.25493.6.55.2552,046
20093.6.56.0/2193.6.56.1 to 93.6.63.25493.6.63.2552,046
20193.6.64.0/2193.6.64.1 to 93.6.71.25493.6.71.2552,046
20293.6.72.0/2193.6.72.1 to 93.6.79.25493.6.79.2552,046
20393.6.80.0/2193.6.80.1 to 93.6.87.25493.6.87.2552,046
20493.6.88.0/2193.6.88.1 to 93.6.95.25493.6.95.2552,046
20593.6.96.0/2193.6.96.1 to 93.6.103.25493.6.103.2552,046
20693.6.104.0/2193.6.104.1 to 93.6.111.25493.6.111.2552,046
20793.6.112.0/2193.6.112.1 to 93.6.119.25493.6.119.2552,046
20893.6.120.0/2193.6.120.1 to 93.6.127.25493.6.127.2552,046
20993.6.128.0/2193.6.128.1 to 93.6.135.25493.6.135.2552,046
21093.6.136.0/2193.6.136.1 to 93.6.143.25493.6.143.2552,046
21193.6.144.0/2193.6.144.1 to 93.6.151.25493.6.151.2552,046
21293.6.152.0/2193.6.152.1 to 93.6.159.25493.6.159.2552,046
21393.6.160.0/2193.6.160.1 to 93.6.167.25493.6.167.2552,046
21493.6.168.0/2193.6.168.1 to 93.6.175.25493.6.175.2552,046
21593.6.176.0/2193.6.176.1 to 93.6.183.25493.6.183.2552,046
21693.6.184.0/2193.6.184.1 to 93.6.191.25493.6.191.2552,046
21793.6.192.0/2193.6.192.1 to 93.6.199.25493.6.199.2552,046
21893.6.200.0/2193.6.200.1 to 93.6.207.25493.6.207.2552,046
21993.6.208.0/2193.6.208.1 to 93.6.215.25493.6.215.2552,046
22093.6.216.0/2193.6.216.1 to 93.6.223.25493.6.223.2552,046
22193.6.224.0/2193.6.224.1 to 93.6.231.25493.6.231.2552,046
22293.6.232.0/2193.6.232.1 to 93.6.239.25493.6.239.2552,046
22393.6.240.0/2193.6.240.1 to 93.6.247.25493.6.247.2552,046
22493.6.248.0/2193.6.248.1 to 93.6.255.25493.6.255.2552,046
22593.7.0.0/2193.7.0.1 to 93.7.7.25493.7.7.2552,046
22693.7.8.0/2193.7.8.1 to 93.7.15.25493.7.15.2552,046
22793.7.16.0/2193.7.16.1 to 93.7.23.25493.7.23.2552,046
22893.7.24.0/2193.7.24.1 to 93.7.31.25493.7.31.2552,046
22993.7.32.0/2193.7.32.1 to 93.7.39.25493.7.39.2552,046
23093.7.40.0/2193.7.40.1 to 93.7.47.25493.7.47.2552,046
23193.7.48.0/2193.7.48.1 to 93.7.55.25493.7.55.2552,046
23293.7.56.0/2193.7.56.1 to 93.7.63.25493.7.63.2552,046
23393.7.64.0/2193.7.64.1 to 93.7.71.25493.7.71.2552,046
23493.7.72.0/2193.7.72.1 to 93.7.79.25493.7.79.2552,046
23593.7.80.0/2193.7.80.1 to 93.7.87.25493.7.87.2552,046
23693.7.88.0/2193.7.88.1 to 93.7.95.25493.7.95.2552,046
23793.7.96.0/2193.7.96.1 to 93.7.103.25493.7.103.2552,046
23893.7.104.0/2193.7.104.1 to 93.7.111.25493.7.111.2552,046
23993.7.112.0/2193.7.112.1 to 93.7.119.25493.7.119.2552,046
24093.7.120.0/2193.7.120.1 to 93.7.127.25493.7.127.2552,046
24193.7.128.0/2193.7.128.1 to 93.7.135.25493.7.135.2552,046
24293.7.136.0/2193.7.136.1 to 93.7.143.25493.7.143.2552,046
24393.7.144.0/2193.7.144.1 to 93.7.151.25493.7.151.2552,046
24493.7.152.0/2193.7.152.1 to 93.7.159.25493.7.159.2552,046
24593.7.160.0/2193.7.160.1 to 93.7.167.25493.7.167.2552,046
24693.7.168.0/2193.7.168.1 to 93.7.175.25493.7.175.2552,046
24793.7.176.0/2193.7.176.1 to 93.7.183.25493.7.183.2552,046
24893.7.184.0/2193.7.184.1 to 93.7.191.25493.7.191.2552,046
24993.7.192.0/2193.7.192.1 to 93.7.199.25493.7.199.2552,046
25093.7.200.0/2193.7.200.1 to 93.7.207.25493.7.207.2552,046
25193.7.208.0/2193.7.208.1 to 93.7.215.25493.7.215.2552,046
25293.7.216.0/2193.7.216.1 to 93.7.223.25493.7.223.2552,046
25393.7.224.0/2193.7.224.1 to 93.7.231.25493.7.231.2552,046
25493.7.232.0/2193.7.232.1 to 93.7.239.25493.7.239.2552,046
25593.7.240.0/2193.7.240.1 to 93.7.247.25493.7.247.2552,046
25693.7.248.0/2193.7.248.1 to 93.7.255.25493.7.255.2552,046

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.