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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.

Network81.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
81.76.0.0
Broadcast address
81.79.255.255
First usable
81.76.0.1
Last usable
81.79.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 514C0000 · Integer 1363935232 to 1364197375
Reverse DNS zones
76.81.in-addr.arpa
77.81.in-addr.arpa
78.81.in-addr.arpa
79.81.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010001.01001100.00000000.0000000081.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01010001.01001100.00000000.0000000081.76.0.0
Broadcast01010001.01001111.11111111.1111111181.79.255.255
Split into smaller subnets/22
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

81.76.0.0/14 makes 256 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
181.76.0.0/2281.76.0.1 to 81.76.3.25481.76.3.2551,022
281.76.4.0/2281.76.4.1 to 81.76.7.25481.76.7.2551,022
381.76.8.0/2281.76.8.1 to 81.76.11.25481.76.11.2551,022
481.76.12.0/2281.76.12.1 to 81.76.15.25481.76.15.2551,022
581.76.16.0/2281.76.16.1 to 81.76.19.25481.76.19.2551,022
681.76.20.0/2281.76.20.1 to 81.76.23.25481.76.23.2551,022
781.76.24.0/2281.76.24.1 to 81.76.27.25481.76.27.2551,022
881.76.28.0/2281.76.28.1 to 81.76.31.25481.76.31.2551,022
981.76.32.0/2281.76.32.1 to 81.76.35.25481.76.35.2551,022
1081.76.36.0/2281.76.36.1 to 81.76.39.25481.76.39.2551,022
1181.76.40.0/2281.76.40.1 to 81.76.43.25481.76.43.2551,022
1281.76.44.0/2281.76.44.1 to 81.76.47.25481.76.47.2551,022
1381.76.48.0/2281.76.48.1 to 81.76.51.25481.76.51.2551,022
1481.76.52.0/2281.76.52.1 to 81.76.55.25481.76.55.2551,022
1581.76.56.0/2281.76.56.1 to 81.76.59.25481.76.59.2551,022
1681.76.60.0/2281.76.60.1 to 81.76.63.25481.76.63.2551,022
1781.76.64.0/2281.76.64.1 to 81.76.67.25481.76.67.2551,022
1881.76.68.0/2281.76.68.1 to 81.76.71.25481.76.71.2551,022
1981.76.72.0/2281.76.72.1 to 81.76.75.25481.76.75.2551,022
2081.76.76.0/2281.76.76.1 to 81.76.79.25481.76.79.2551,022
2181.76.80.0/2281.76.80.1 to 81.76.83.25481.76.83.2551,022
2281.76.84.0/2281.76.84.1 to 81.76.87.25481.76.87.2551,022
2381.76.88.0/2281.76.88.1 to 81.76.91.25481.76.91.2551,022
2481.76.92.0/2281.76.92.1 to 81.76.95.25481.76.95.2551,022
2581.76.96.0/2281.76.96.1 to 81.76.99.25481.76.99.2551,022
2681.76.100.0/2281.76.100.1 to 81.76.103.25481.76.103.2551,022
2781.76.104.0/2281.76.104.1 to 81.76.107.25481.76.107.2551,022
2881.76.108.0/2281.76.108.1 to 81.76.111.25481.76.111.2551,022
2981.76.112.0/2281.76.112.1 to 81.76.115.25481.76.115.2551,022
3081.76.116.0/2281.76.116.1 to 81.76.119.25481.76.119.2551,022
3181.76.120.0/2281.76.120.1 to 81.76.123.25481.76.123.2551,022
3281.76.124.0/2281.76.124.1 to 81.76.127.25481.76.127.2551,022
3381.76.128.0/2281.76.128.1 to 81.76.131.25481.76.131.2551,022
3481.76.132.0/2281.76.132.1 to 81.76.135.25481.76.135.2551,022
3581.76.136.0/2281.76.136.1 to 81.76.139.25481.76.139.2551,022
3681.76.140.0/2281.76.140.1 to 81.76.143.25481.76.143.2551,022
3781.76.144.0/2281.76.144.1 to 81.76.147.25481.76.147.2551,022
3881.76.148.0/2281.76.148.1 to 81.76.151.25481.76.151.2551,022
3981.76.152.0/2281.76.152.1 to 81.76.155.25481.76.155.2551,022
4081.76.156.0/2281.76.156.1 to 81.76.159.25481.76.159.2551,022
4181.76.160.0/2281.76.160.1 to 81.76.163.25481.76.163.2551,022
4281.76.164.0/2281.76.164.1 to 81.76.167.25481.76.167.2551,022
4381.76.168.0/2281.76.168.1 to 81.76.171.25481.76.171.2551,022
4481.76.172.0/2281.76.172.1 to 81.76.175.25481.76.175.2551,022
4581.76.176.0/2281.76.176.1 to 81.76.179.25481.76.179.2551,022
4681.76.180.0/2281.76.180.1 to 81.76.183.25481.76.183.2551,022
4781.76.184.0/2281.76.184.1 to 81.76.187.25481.76.187.2551,022
4881.76.188.0/2281.76.188.1 to 81.76.191.25481.76.191.2551,022
4981.76.192.0/2281.76.192.1 to 81.76.195.25481.76.195.2551,022
5081.76.196.0/2281.76.196.1 to 81.76.199.25481.76.199.2551,022
5181.76.200.0/2281.76.200.1 to 81.76.203.25481.76.203.2551,022
5281.76.204.0/2281.76.204.1 to 81.76.207.25481.76.207.2551,022
5381.76.208.0/2281.76.208.1 to 81.76.211.25481.76.211.2551,022
5481.76.212.0/2281.76.212.1 to 81.76.215.25481.76.215.2551,022
5581.76.216.0/2281.76.216.1 to 81.76.219.25481.76.219.2551,022
5681.76.220.0/2281.76.220.1 to 81.76.223.25481.76.223.2551,022
5781.76.224.0/2281.76.224.1 to 81.76.227.25481.76.227.2551,022
5881.76.228.0/2281.76.228.1 to 81.76.231.25481.76.231.2551,022
5981.76.232.0/2281.76.232.1 to 81.76.235.25481.76.235.2551,022
6081.76.236.0/2281.76.236.1 to 81.76.239.25481.76.239.2551,022
6181.76.240.0/2281.76.240.1 to 81.76.243.25481.76.243.2551,022
6281.76.244.0/2281.76.244.1 to 81.76.247.25481.76.247.2551,022
6381.76.248.0/2281.76.248.1 to 81.76.251.25481.76.251.2551,022
6481.76.252.0/2281.76.252.1 to 81.76.255.25481.76.255.2551,022
6581.77.0.0/2281.77.0.1 to 81.77.3.25481.77.3.2551,022
6681.77.4.0/2281.77.4.1 to 81.77.7.25481.77.7.2551,022
6781.77.8.0/2281.77.8.1 to 81.77.11.25481.77.11.2551,022
6881.77.12.0/2281.77.12.1 to 81.77.15.25481.77.15.2551,022
6981.77.16.0/2281.77.16.1 to 81.77.19.25481.77.19.2551,022
7081.77.20.0/2281.77.20.1 to 81.77.23.25481.77.23.2551,022
7181.77.24.0/2281.77.24.1 to 81.77.27.25481.77.27.2551,022
7281.77.28.0/2281.77.28.1 to 81.77.31.25481.77.31.2551,022
7381.77.32.0/2281.77.32.1 to 81.77.35.25481.77.35.2551,022
7481.77.36.0/2281.77.36.1 to 81.77.39.25481.77.39.2551,022
7581.77.40.0/2281.77.40.1 to 81.77.43.25481.77.43.2551,022
7681.77.44.0/2281.77.44.1 to 81.77.47.25481.77.47.2551,022
7781.77.48.0/2281.77.48.1 to 81.77.51.25481.77.51.2551,022
7881.77.52.0/2281.77.52.1 to 81.77.55.25481.77.55.2551,022
7981.77.56.0/2281.77.56.1 to 81.77.59.25481.77.59.2551,022
8081.77.60.0/2281.77.60.1 to 81.77.63.25481.77.63.2551,022
8181.77.64.0/2281.77.64.1 to 81.77.67.25481.77.67.2551,022
8281.77.68.0/2281.77.68.1 to 81.77.71.25481.77.71.2551,022
8381.77.72.0/2281.77.72.1 to 81.77.75.25481.77.75.2551,022
8481.77.76.0/2281.77.76.1 to 81.77.79.25481.77.79.2551,022
8581.77.80.0/2281.77.80.1 to 81.77.83.25481.77.83.2551,022
8681.77.84.0/2281.77.84.1 to 81.77.87.25481.77.87.2551,022
8781.77.88.0/2281.77.88.1 to 81.77.91.25481.77.91.2551,022
8881.77.92.0/2281.77.92.1 to 81.77.95.25481.77.95.2551,022
8981.77.96.0/2281.77.96.1 to 81.77.99.25481.77.99.2551,022
9081.77.100.0/2281.77.100.1 to 81.77.103.25481.77.103.2551,022
9181.77.104.0/2281.77.104.1 to 81.77.107.25481.77.107.2551,022
9281.77.108.0/2281.77.108.1 to 81.77.111.25481.77.111.2551,022
9381.77.112.0/2281.77.112.1 to 81.77.115.25481.77.115.2551,022
9481.77.116.0/2281.77.116.1 to 81.77.119.25481.77.119.2551,022
9581.77.120.0/2281.77.120.1 to 81.77.123.25481.77.123.2551,022
9681.77.124.0/2281.77.124.1 to 81.77.127.25481.77.127.2551,022
9781.77.128.0/2281.77.128.1 to 81.77.131.25481.77.131.2551,022
9881.77.132.0/2281.77.132.1 to 81.77.135.25481.77.135.2551,022
9981.77.136.0/2281.77.136.1 to 81.77.139.25481.77.139.2551,022
10081.77.140.0/2281.77.140.1 to 81.77.143.25481.77.143.2551,022
10181.77.144.0/2281.77.144.1 to 81.77.147.25481.77.147.2551,022
10281.77.148.0/2281.77.148.1 to 81.77.151.25481.77.151.2551,022
10381.77.152.0/2281.77.152.1 to 81.77.155.25481.77.155.2551,022
10481.77.156.0/2281.77.156.1 to 81.77.159.25481.77.159.2551,022
10581.77.160.0/2281.77.160.1 to 81.77.163.25481.77.163.2551,022
10681.77.164.0/2281.77.164.1 to 81.77.167.25481.77.167.2551,022
10781.77.168.0/2281.77.168.1 to 81.77.171.25481.77.171.2551,022
10881.77.172.0/2281.77.172.1 to 81.77.175.25481.77.175.2551,022
10981.77.176.0/2281.77.176.1 to 81.77.179.25481.77.179.2551,022
11081.77.180.0/2281.77.180.1 to 81.77.183.25481.77.183.2551,022
11181.77.184.0/2281.77.184.1 to 81.77.187.25481.77.187.2551,022
11281.77.188.0/2281.77.188.1 to 81.77.191.25481.77.191.2551,022
11381.77.192.0/2281.77.192.1 to 81.77.195.25481.77.195.2551,022
11481.77.196.0/2281.77.196.1 to 81.77.199.25481.77.199.2551,022
11581.77.200.0/2281.77.200.1 to 81.77.203.25481.77.203.2551,022
11681.77.204.0/2281.77.204.1 to 81.77.207.25481.77.207.2551,022
11781.77.208.0/2281.77.208.1 to 81.77.211.25481.77.211.2551,022
11881.77.212.0/2281.77.212.1 to 81.77.215.25481.77.215.2551,022
11981.77.216.0/2281.77.216.1 to 81.77.219.25481.77.219.2551,022
12081.77.220.0/2281.77.220.1 to 81.77.223.25481.77.223.2551,022
12181.77.224.0/2281.77.224.1 to 81.77.227.25481.77.227.2551,022
12281.77.228.0/2281.77.228.1 to 81.77.231.25481.77.231.2551,022
12381.77.232.0/2281.77.232.1 to 81.77.235.25481.77.235.2551,022
12481.77.236.0/2281.77.236.1 to 81.77.239.25481.77.239.2551,022
12581.77.240.0/2281.77.240.1 to 81.77.243.25481.77.243.2551,022
12681.77.244.0/2281.77.244.1 to 81.77.247.25481.77.247.2551,022
12781.77.248.0/2281.77.248.1 to 81.77.251.25481.77.251.2551,022
12881.77.252.0/2281.77.252.1 to 81.77.255.25481.77.255.2551,022
12981.78.0.0/2281.78.0.1 to 81.78.3.25481.78.3.2551,022
13081.78.4.0/2281.78.4.1 to 81.78.7.25481.78.7.2551,022
13181.78.8.0/2281.78.8.1 to 81.78.11.25481.78.11.2551,022
13281.78.12.0/2281.78.12.1 to 81.78.15.25481.78.15.2551,022
13381.78.16.0/2281.78.16.1 to 81.78.19.25481.78.19.2551,022
13481.78.20.0/2281.78.20.1 to 81.78.23.25481.78.23.2551,022
13581.78.24.0/2281.78.24.1 to 81.78.27.25481.78.27.2551,022
13681.78.28.0/2281.78.28.1 to 81.78.31.25481.78.31.2551,022
13781.78.32.0/2281.78.32.1 to 81.78.35.25481.78.35.2551,022
13881.78.36.0/2281.78.36.1 to 81.78.39.25481.78.39.2551,022
13981.78.40.0/2281.78.40.1 to 81.78.43.25481.78.43.2551,022
14081.78.44.0/2281.78.44.1 to 81.78.47.25481.78.47.2551,022
14181.78.48.0/2281.78.48.1 to 81.78.51.25481.78.51.2551,022
14281.78.52.0/2281.78.52.1 to 81.78.55.25481.78.55.2551,022
14381.78.56.0/2281.78.56.1 to 81.78.59.25481.78.59.2551,022
14481.78.60.0/2281.78.60.1 to 81.78.63.25481.78.63.2551,022
14581.78.64.0/2281.78.64.1 to 81.78.67.25481.78.67.2551,022
14681.78.68.0/2281.78.68.1 to 81.78.71.25481.78.71.2551,022
14781.78.72.0/2281.78.72.1 to 81.78.75.25481.78.75.2551,022
14881.78.76.0/2281.78.76.1 to 81.78.79.25481.78.79.2551,022
14981.78.80.0/2281.78.80.1 to 81.78.83.25481.78.83.2551,022
15081.78.84.0/2281.78.84.1 to 81.78.87.25481.78.87.2551,022
15181.78.88.0/2281.78.88.1 to 81.78.91.25481.78.91.2551,022
15281.78.92.0/2281.78.92.1 to 81.78.95.25481.78.95.2551,022
15381.78.96.0/2281.78.96.1 to 81.78.99.25481.78.99.2551,022
15481.78.100.0/2281.78.100.1 to 81.78.103.25481.78.103.2551,022
15581.78.104.0/2281.78.104.1 to 81.78.107.25481.78.107.2551,022
15681.78.108.0/2281.78.108.1 to 81.78.111.25481.78.111.2551,022
15781.78.112.0/2281.78.112.1 to 81.78.115.25481.78.115.2551,022
15881.78.116.0/2281.78.116.1 to 81.78.119.25481.78.119.2551,022
15981.78.120.0/2281.78.120.1 to 81.78.123.25481.78.123.2551,022
16081.78.124.0/2281.78.124.1 to 81.78.127.25481.78.127.2551,022
16181.78.128.0/2281.78.128.1 to 81.78.131.25481.78.131.2551,022
16281.78.132.0/2281.78.132.1 to 81.78.135.25481.78.135.2551,022
16381.78.136.0/2281.78.136.1 to 81.78.139.25481.78.139.2551,022
16481.78.140.0/2281.78.140.1 to 81.78.143.25481.78.143.2551,022
16581.78.144.0/2281.78.144.1 to 81.78.147.25481.78.147.2551,022
16681.78.148.0/2281.78.148.1 to 81.78.151.25481.78.151.2551,022
16781.78.152.0/2281.78.152.1 to 81.78.155.25481.78.155.2551,022
16881.78.156.0/2281.78.156.1 to 81.78.159.25481.78.159.2551,022
16981.78.160.0/2281.78.160.1 to 81.78.163.25481.78.163.2551,022
17081.78.164.0/2281.78.164.1 to 81.78.167.25481.78.167.2551,022
17181.78.168.0/2281.78.168.1 to 81.78.171.25481.78.171.2551,022
17281.78.172.0/2281.78.172.1 to 81.78.175.25481.78.175.2551,022
17381.78.176.0/2281.78.176.1 to 81.78.179.25481.78.179.2551,022
17481.78.180.0/2281.78.180.1 to 81.78.183.25481.78.183.2551,022
17581.78.184.0/2281.78.184.1 to 81.78.187.25481.78.187.2551,022
17681.78.188.0/2281.78.188.1 to 81.78.191.25481.78.191.2551,022
17781.78.192.0/2281.78.192.1 to 81.78.195.25481.78.195.2551,022
17881.78.196.0/2281.78.196.1 to 81.78.199.25481.78.199.2551,022
17981.78.200.0/2281.78.200.1 to 81.78.203.25481.78.203.2551,022
18081.78.204.0/2281.78.204.1 to 81.78.207.25481.78.207.2551,022
18181.78.208.0/2281.78.208.1 to 81.78.211.25481.78.211.2551,022
18281.78.212.0/2281.78.212.1 to 81.78.215.25481.78.215.2551,022
18381.78.216.0/2281.78.216.1 to 81.78.219.25481.78.219.2551,022
18481.78.220.0/2281.78.220.1 to 81.78.223.25481.78.223.2551,022
18581.78.224.0/2281.78.224.1 to 81.78.227.25481.78.227.2551,022
18681.78.228.0/2281.78.228.1 to 81.78.231.25481.78.231.2551,022
18781.78.232.0/2281.78.232.1 to 81.78.235.25481.78.235.2551,022
18881.78.236.0/2281.78.236.1 to 81.78.239.25481.78.239.2551,022
18981.78.240.0/2281.78.240.1 to 81.78.243.25481.78.243.2551,022
19081.78.244.0/2281.78.244.1 to 81.78.247.25481.78.247.2551,022
19181.78.248.0/2281.78.248.1 to 81.78.251.25481.78.251.2551,022
19281.78.252.0/2281.78.252.1 to 81.78.255.25481.78.255.2551,022
19381.79.0.0/2281.79.0.1 to 81.79.3.25481.79.3.2551,022
19481.79.4.0/2281.79.4.1 to 81.79.7.25481.79.7.2551,022
19581.79.8.0/2281.79.8.1 to 81.79.11.25481.79.11.2551,022
19681.79.12.0/2281.79.12.1 to 81.79.15.25481.79.15.2551,022
19781.79.16.0/2281.79.16.1 to 81.79.19.25481.79.19.2551,022
19881.79.20.0/2281.79.20.1 to 81.79.23.25481.79.23.2551,022
19981.79.24.0/2281.79.24.1 to 81.79.27.25481.79.27.2551,022
20081.79.28.0/2281.79.28.1 to 81.79.31.25481.79.31.2551,022
20181.79.32.0/2281.79.32.1 to 81.79.35.25481.79.35.2551,022
20281.79.36.0/2281.79.36.1 to 81.79.39.25481.79.39.2551,022
20381.79.40.0/2281.79.40.1 to 81.79.43.25481.79.43.2551,022
20481.79.44.0/2281.79.44.1 to 81.79.47.25481.79.47.2551,022
20581.79.48.0/2281.79.48.1 to 81.79.51.25481.79.51.2551,022
20681.79.52.0/2281.79.52.1 to 81.79.55.25481.79.55.2551,022
20781.79.56.0/2281.79.56.1 to 81.79.59.25481.79.59.2551,022
20881.79.60.0/2281.79.60.1 to 81.79.63.25481.79.63.2551,022
20981.79.64.0/2281.79.64.1 to 81.79.67.25481.79.67.2551,022
21081.79.68.0/2281.79.68.1 to 81.79.71.25481.79.71.2551,022
21181.79.72.0/2281.79.72.1 to 81.79.75.25481.79.75.2551,022
21281.79.76.0/2281.79.76.1 to 81.79.79.25481.79.79.2551,022
21381.79.80.0/2281.79.80.1 to 81.79.83.25481.79.83.2551,022
21481.79.84.0/2281.79.84.1 to 81.79.87.25481.79.87.2551,022
21581.79.88.0/2281.79.88.1 to 81.79.91.25481.79.91.2551,022
21681.79.92.0/2281.79.92.1 to 81.79.95.25481.79.95.2551,022
21781.79.96.0/2281.79.96.1 to 81.79.99.25481.79.99.2551,022
21881.79.100.0/2281.79.100.1 to 81.79.103.25481.79.103.2551,022
21981.79.104.0/2281.79.104.1 to 81.79.107.25481.79.107.2551,022
22081.79.108.0/2281.79.108.1 to 81.79.111.25481.79.111.2551,022
22181.79.112.0/2281.79.112.1 to 81.79.115.25481.79.115.2551,022
22281.79.116.0/2281.79.116.1 to 81.79.119.25481.79.119.2551,022
22381.79.120.0/2281.79.120.1 to 81.79.123.25481.79.123.2551,022
22481.79.124.0/2281.79.124.1 to 81.79.127.25481.79.127.2551,022
22581.79.128.0/2281.79.128.1 to 81.79.131.25481.79.131.2551,022
22681.79.132.0/2281.79.132.1 to 81.79.135.25481.79.135.2551,022
22781.79.136.0/2281.79.136.1 to 81.79.139.25481.79.139.2551,022
22881.79.140.0/2281.79.140.1 to 81.79.143.25481.79.143.2551,022
22981.79.144.0/2281.79.144.1 to 81.79.147.25481.79.147.2551,022
23081.79.148.0/2281.79.148.1 to 81.79.151.25481.79.151.2551,022
23181.79.152.0/2281.79.152.1 to 81.79.155.25481.79.155.2551,022
23281.79.156.0/2281.79.156.1 to 81.79.159.25481.79.159.2551,022
23381.79.160.0/2281.79.160.1 to 81.79.163.25481.79.163.2551,022
23481.79.164.0/2281.79.164.1 to 81.79.167.25481.79.167.2551,022
23581.79.168.0/2281.79.168.1 to 81.79.171.25481.79.171.2551,022
23681.79.172.0/2281.79.172.1 to 81.79.175.25481.79.175.2551,022
23781.79.176.0/2281.79.176.1 to 81.79.179.25481.79.179.2551,022
23881.79.180.0/2281.79.180.1 to 81.79.183.25481.79.183.2551,022
23981.79.184.0/2281.79.184.1 to 81.79.187.25481.79.187.2551,022
24081.79.188.0/2281.79.188.1 to 81.79.191.25481.79.191.2551,022
24181.79.192.0/2281.79.192.1 to 81.79.195.25481.79.195.2551,022
24281.79.196.0/2281.79.196.1 to 81.79.199.25481.79.199.2551,022
24381.79.200.0/2281.79.200.1 to 81.79.203.25481.79.203.2551,022
24481.79.204.0/2281.79.204.1 to 81.79.207.25481.79.207.2551,022
24581.79.208.0/2281.79.208.1 to 81.79.211.25481.79.211.2551,022
24681.79.212.0/2281.79.212.1 to 81.79.215.25481.79.215.2551,022
24781.79.216.0/2281.79.216.1 to 81.79.219.25481.79.219.2551,022
24881.79.220.0/2281.79.220.1 to 81.79.223.25481.79.223.2551,022
24981.79.224.0/2281.79.224.1 to 81.79.227.25481.79.227.2551,022
25081.79.228.0/2281.79.228.1 to 81.79.231.25481.79.231.2551,022
25181.79.232.0/2281.79.232.1 to 81.79.235.25481.79.235.2551,022
25281.79.236.0/2281.79.236.1 to 81.79.239.25481.79.239.2551,022
25381.79.240.0/2281.79.240.1 to 81.79.243.25481.79.243.2551,022
25481.79.244.0/2281.79.244.1 to 81.79.247.25481.79.247.2551,022
25581.79.248.0/2281.79.248.1 to 81.79.251.25481.79.251.2551,022
25681.79.252.0/2281.79.252.1 to 81.79.255.25481.79.255.2551,022

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.