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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.

Network80.0.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
80.0.0.0
Broadcast address
80.3.255.255
First usable
80.0.0.1
Last usable
80.3.255.254
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 50000000 · Integer 1342177280 to 1342439423
Reverse DNS zones
0.80.in-addr.arpa
1.80.in-addr.arpa
2.80.in-addr.arpa
3.80.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
Address01010000.00000000.00000000.0000000080.0.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01010000.00000000.00000000.0000000080.0.0.0
Broadcast01010000.00000011.11111111.1111111180.3.255.255
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)

80.0.0.0/14 makes 256 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
180.0.0.0/2280.0.0.1 to 80.0.3.25480.0.3.2551,022
280.0.4.0/2280.0.4.1 to 80.0.7.25480.0.7.2551,022
380.0.8.0/2280.0.8.1 to 80.0.11.25480.0.11.2551,022
480.0.12.0/2280.0.12.1 to 80.0.15.25480.0.15.2551,022
580.0.16.0/2280.0.16.1 to 80.0.19.25480.0.19.2551,022
680.0.20.0/2280.0.20.1 to 80.0.23.25480.0.23.2551,022
780.0.24.0/2280.0.24.1 to 80.0.27.25480.0.27.2551,022
880.0.28.0/2280.0.28.1 to 80.0.31.25480.0.31.2551,022
980.0.32.0/2280.0.32.1 to 80.0.35.25480.0.35.2551,022
1080.0.36.0/2280.0.36.1 to 80.0.39.25480.0.39.2551,022
1180.0.40.0/2280.0.40.1 to 80.0.43.25480.0.43.2551,022
1280.0.44.0/2280.0.44.1 to 80.0.47.25480.0.47.2551,022
1380.0.48.0/2280.0.48.1 to 80.0.51.25480.0.51.2551,022
1480.0.52.0/2280.0.52.1 to 80.0.55.25480.0.55.2551,022
1580.0.56.0/2280.0.56.1 to 80.0.59.25480.0.59.2551,022
1680.0.60.0/2280.0.60.1 to 80.0.63.25480.0.63.2551,022
1780.0.64.0/2280.0.64.1 to 80.0.67.25480.0.67.2551,022
1880.0.68.0/2280.0.68.1 to 80.0.71.25480.0.71.2551,022
1980.0.72.0/2280.0.72.1 to 80.0.75.25480.0.75.2551,022
2080.0.76.0/2280.0.76.1 to 80.0.79.25480.0.79.2551,022
2180.0.80.0/2280.0.80.1 to 80.0.83.25480.0.83.2551,022
2280.0.84.0/2280.0.84.1 to 80.0.87.25480.0.87.2551,022
2380.0.88.0/2280.0.88.1 to 80.0.91.25480.0.91.2551,022
2480.0.92.0/2280.0.92.1 to 80.0.95.25480.0.95.2551,022
2580.0.96.0/2280.0.96.1 to 80.0.99.25480.0.99.2551,022
2680.0.100.0/2280.0.100.1 to 80.0.103.25480.0.103.2551,022
2780.0.104.0/2280.0.104.1 to 80.0.107.25480.0.107.2551,022
2880.0.108.0/2280.0.108.1 to 80.0.111.25480.0.111.2551,022
2980.0.112.0/2280.0.112.1 to 80.0.115.25480.0.115.2551,022
3080.0.116.0/2280.0.116.1 to 80.0.119.25480.0.119.2551,022
3180.0.120.0/2280.0.120.1 to 80.0.123.25480.0.123.2551,022
3280.0.124.0/2280.0.124.1 to 80.0.127.25480.0.127.2551,022
3380.0.128.0/2280.0.128.1 to 80.0.131.25480.0.131.2551,022
3480.0.132.0/2280.0.132.1 to 80.0.135.25480.0.135.2551,022
3580.0.136.0/2280.0.136.1 to 80.0.139.25480.0.139.2551,022
3680.0.140.0/2280.0.140.1 to 80.0.143.25480.0.143.2551,022
3780.0.144.0/2280.0.144.1 to 80.0.147.25480.0.147.2551,022
3880.0.148.0/2280.0.148.1 to 80.0.151.25480.0.151.2551,022
3980.0.152.0/2280.0.152.1 to 80.0.155.25480.0.155.2551,022
4080.0.156.0/2280.0.156.1 to 80.0.159.25480.0.159.2551,022
4180.0.160.0/2280.0.160.1 to 80.0.163.25480.0.163.2551,022
4280.0.164.0/2280.0.164.1 to 80.0.167.25480.0.167.2551,022
4380.0.168.0/2280.0.168.1 to 80.0.171.25480.0.171.2551,022
4480.0.172.0/2280.0.172.1 to 80.0.175.25480.0.175.2551,022
4580.0.176.0/2280.0.176.1 to 80.0.179.25480.0.179.2551,022
4680.0.180.0/2280.0.180.1 to 80.0.183.25480.0.183.2551,022
4780.0.184.0/2280.0.184.1 to 80.0.187.25480.0.187.2551,022
4880.0.188.0/2280.0.188.1 to 80.0.191.25480.0.191.2551,022
4980.0.192.0/2280.0.192.1 to 80.0.195.25480.0.195.2551,022
5080.0.196.0/2280.0.196.1 to 80.0.199.25480.0.199.2551,022
5180.0.200.0/2280.0.200.1 to 80.0.203.25480.0.203.2551,022
5280.0.204.0/2280.0.204.1 to 80.0.207.25480.0.207.2551,022
5380.0.208.0/2280.0.208.1 to 80.0.211.25480.0.211.2551,022
5480.0.212.0/2280.0.212.1 to 80.0.215.25480.0.215.2551,022
5580.0.216.0/2280.0.216.1 to 80.0.219.25480.0.219.2551,022
5680.0.220.0/2280.0.220.1 to 80.0.223.25480.0.223.2551,022
5780.0.224.0/2280.0.224.1 to 80.0.227.25480.0.227.2551,022
5880.0.228.0/2280.0.228.1 to 80.0.231.25480.0.231.2551,022
5980.0.232.0/2280.0.232.1 to 80.0.235.25480.0.235.2551,022
6080.0.236.0/2280.0.236.1 to 80.0.239.25480.0.239.2551,022
6180.0.240.0/2280.0.240.1 to 80.0.243.25480.0.243.2551,022
6280.0.244.0/2280.0.244.1 to 80.0.247.25480.0.247.2551,022
6380.0.248.0/2280.0.248.1 to 80.0.251.25480.0.251.2551,022
6480.0.252.0/2280.0.252.1 to 80.0.255.25480.0.255.2551,022
6580.1.0.0/2280.1.0.1 to 80.1.3.25480.1.3.2551,022
6680.1.4.0/2280.1.4.1 to 80.1.7.25480.1.7.2551,022
6780.1.8.0/2280.1.8.1 to 80.1.11.25480.1.11.2551,022
6880.1.12.0/2280.1.12.1 to 80.1.15.25480.1.15.2551,022
6980.1.16.0/2280.1.16.1 to 80.1.19.25480.1.19.2551,022
7080.1.20.0/2280.1.20.1 to 80.1.23.25480.1.23.2551,022
7180.1.24.0/2280.1.24.1 to 80.1.27.25480.1.27.2551,022
7280.1.28.0/2280.1.28.1 to 80.1.31.25480.1.31.2551,022
7380.1.32.0/2280.1.32.1 to 80.1.35.25480.1.35.2551,022
7480.1.36.0/2280.1.36.1 to 80.1.39.25480.1.39.2551,022
7580.1.40.0/2280.1.40.1 to 80.1.43.25480.1.43.2551,022
7680.1.44.0/2280.1.44.1 to 80.1.47.25480.1.47.2551,022
7780.1.48.0/2280.1.48.1 to 80.1.51.25480.1.51.2551,022
7880.1.52.0/2280.1.52.1 to 80.1.55.25480.1.55.2551,022
7980.1.56.0/2280.1.56.1 to 80.1.59.25480.1.59.2551,022
8080.1.60.0/2280.1.60.1 to 80.1.63.25480.1.63.2551,022
8180.1.64.0/2280.1.64.1 to 80.1.67.25480.1.67.2551,022
8280.1.68.0/2280.1.68.1 to 80.1.71.25480.1.71.2551,022
8380.1.72.0/2280.1.72.1 to 80.1.75.25480.1.75.2551,022
8480.1.76.0/2280.1.76.1 to 80.1.79.25480.1.79.2551,022
8580.1.80.0/2280.1.80.1 to 80.1.83.25480.1.83.2551,022
8680.1.84.0/2280.1.84.1 to 80.1.87.25480.1.87.2551,022
8780.1.88.0/2280.1.88.1 to 80.1.91.25480.1.91.2551,022
8880.1.92.0/2280.1.92.1 to 80.1.95.25480.1.95.2551,022
8980.1.96.0/2280.1.96.1 to 80.1.99.25480.1.99.2551,022
9080.1.100.0/2280.1.100.1 to 80.1.103.25480.1.103.2551,022
9180.1.104.0/2280.1.104.1 to 80.1.107.25480.1.107.2551,022
9280.1.108.0/2280.1.108.1 to 80.1.111.25480.1.111.2551,022
9380.1.112.0/2280.1.112.1 to 80.1.115.25480.1.115.2551,022
9480.1.116.0/2280.1.116.1 to 80.1.119.25480.1.119.2551,022
9580.1.120.0/2280.1.120.1 to 80.1.123.25480.1.123.2551,022
9680.1.124.0/2280.1.124.1 to 80.1.127.25480.1.127.2551,022
9780.1.128.0/2280.1.128.1 to 80.1.131.25480.1.131.2551,022
9880.1.132.0/2280.1.132.1 to 80.1.135.25480.1.135.2551,022
9980.1.136.0/2280.1.136.1 to 80.1.139.25480.1.139.2551,022
10080.1.140.0/2280.1.140.1 to 80.1.143.25480.1.143.2551,022
10180.1.144.0/2280.1.144.1 to 80.1.147.25480.1.147.2551,022
10280.1.148.0/2280.1.148.1 to 80.1.151.25480.1.151.2551,022
10380.1.152.0/2280.1.152.1 to 80.1.155.25480.1.155.2551,022
10480.1.156.0/2280.1.156.1 to 80.1.159.25480.1.159.2551,022
10580.1.160.0/2280.1.160.1 to 80.1.163.25480.1.163.2551,022
10680.1.164.0/2280.1.164.1 to 80.1.167.25480.1.167.2551,022
10780.1.168.0/2280.1.168.1 to 80.1.171.25480.1.171.2551,022
10880.1.172.0/2280.1.172.1 to 80.1.175.25480.1.175.2551,022
10980.1.176.0/2280.1.176.1 to 80.1.179.25480.1.179.2551,022
11080.1.180.0/2280.1.180.1 to 80.1.183.25480.1.183.2551,022
11180.1.184.0/2280.1.184.1 to 80.1.187.25480.1.187.2551,022
11280.1.188.0/2280.1.188.1 to 80.1.191.25480.1.191.2551,022
11380.1.192.0/2280.1.192.1 to 80.1.195.25480.1.195.2551,022
11480.1.196.0/2280.1.196.1 to 80.1.199.25480.1.199.2551,022
11580.1.200.0/2280.1.200.1 to 80.1.203.25480.1.203.2551,022
11680.1.204.0/2280.1.204.1 to 80.1.207.25480.1.207.2551,022
11780.1.208.0/2280.1.208.1 to 80.1.211.25480.1.211.2551,022
11880.1.212.0/2280.1.212.1 to 80.1.215.25480.1.215.2551,022
11980.1.216.0/2280.1.216.1 to 80.1.219.25480.1.219.2551,022
12080.1.220.0/2280.1.220.1 to 80.1.223.25480.1.223.2551,022
12180.1.224.0/2280.1.224.1 to 80.1.227.25480.1.227.2551,022
12280.1.228.0/2280.1.228.1 to 80.1.231.25480.1.231.2551,022
12380.1.232.0/2280.1.232.1 to 80.1.235.25480.1.235.2551,022
12480.1.236.0/2280.1.236.1 to 80.1.239.25480.1.239.2551,022
12580.1.240.0/2280.1.240.1 to 80.1.243.25480.1.243.2551,022
12680.1.244.0/2280.1.244.1 to 80.1.247.25480.1.247.2551,022
12780.1.248.0/2280.1.248.1 to 80.1.251.25480.1.251.2551,022
12880.1.252.0/2280.1.252.1 to 80.1.255.25480.1.255.2551,022
12980.2.0.0/2280.2.0.1 to 80.2.3.25480.2.3.2551,022
13080.2.4.0/2280.2.4.1 to 80.2.7.25480.2.7.2551,022
13180.2.8.0/2280.2.8.1 to 80.2.11.25480.2.11.2551,022
13280.2.12.0/2280.2.12.1 to 80.2.15.25480.2.15.2551,022
13380.2.16.0/2280.2.16.1 to 80.2.19.25480.2.19.2551,022
13480.2.20.0/2280.2.20.1 to 80.2.23.25480.2.23.2551,022
13580.2.24.0/2280.2.24.1 to 80.2.27.25480.2.27.2551,022
13680.2.28.0/2280.2.28.1 to 80.2.31.25480.2.31.2551,022
13780.2.32.0/2280.2.32.1 to 80.2.35.25480.2.35.2551,022
13880.2.36.0/2280.2.36.1 to 80.2.39.25480.2.39.2551,022
13980.2.40.0/2280.2.40.1 to 80.2.43.25480.2.43.2551,022
14080.2.44.0/2280.2.44.1 to 80.2.47.25480.2.47.2551,022
14180.2.48.0/2280.2.48.1 to 80.2.51.25480.2.51.2551,022
14280.2.52.0/2280.2.52.1 to 80.2.55.25480.2.55.2551,022
14380.2.56.0/2280.2.56.1 to 80.2.59.25480.2.59.2551,022
14480.2.60.0/2280.2.60.1 to 80.2.63.25480.2.63.2551,022
14580.2.64.0/2280.2.64.1 to 80.2.67.25480.2.67.2551,022
14680.2.68.0/2280.2.68.1 to 80.2.71.25480.2.71.2551,022
14780.2.72.0/2280.2.72.1 to 80.2.75.25480.2.75.2551,022
14880.2.76.0/2280.2.76.1 to 80.2.79.25480.2.79.2551,022
14980.2.80.0/2280.2.80.1 to 80.2.83.25480.2.83.2551,022
15080.2.84.0/2280.2.84.1 to 80.2.87.25480.2.87.2551,022
15180.2.88.0/2280.2.88.1 to 80.2.91.25480.2.91.2551,022
15280.2.92.0/2280.2.92.1 to 80.2.95.25480.2.95.2551,022
15380.2.96.0/2280.2.96.1 to 80.2.99.25480.2.99.2551,022
15480.2.100.0/2280.2.100.1 to 80.2.103.25480.2.103.2551,022
15580.2.104.0/2280.2.104.1 to 80.2.107.25480.2.107.2551,022
15680.2.108.0/2280.2.108.1 to 80.2.111.25480.2.111.2551,022
15780.2.112.0/2280.2.112.1 to 80.2.115.25480.2.115.2551,022
15880.2.116.0/2280.2.116.1 to 80.2.119.25480.2.119.2551,022
15980.2.120.0/2280.2.120.1 to 80.2.123.25480.2.123.2551,022
16080.2.124.0/2280.2.124.1 to 80.2.127.25480.2.127.2551,022
16180.2.128.0/2280.2.128.1 to 80.2.131.25480.2.131.2551,022
16280.2.132.0/2280.2.132.1 to 80.2.135.25480.2.135.2551,022
16380.2.136.0/2280.2.136.1 to 80.2.139.25480.2.139.2551,022
16480.2.140.0/2280.2.140.1 to 80.2.143.25480.2.143.2551,022
16580.2.144.0/2280.2.144.1 to 80.2.147.25480.2.147.2551,022
16680.2.148.0/2280.2.148.1 to 80.2.151.25480.2.151.2551,022
16780.2.152.0/2280.2.152.1 to 80.2.155.25480.2.155.2551,022
16880.2.156.0/2280.2.156.1 to 80.2.159.25480.2.159.2551,022
16980.2.160.0/2280.2.160.1 to 80.2.163.25480.2.163.2551,022
17080.2.164.0/2280.2.164.1 to 80.2.167.25480.2.167.2551,022
17180.2.168.0/2280.2.168.1 to 80.2.171.25480.2.171.2551,022
17280.2.172.0/2280.2.172.1 to 80.2.175.25480.2.175.2551,022
17380.2.176.0/2280.2.176.1 to 80.2.179.25480.2.179.2551,022
17480.2.180.0/2280.2.180.1 to 80.2.183.25480.2.183.2551,022
17580.2.184.0/2280.2.184.1 to 80.2.187.25480.2.187.2551,022
17680.2.188.0/2280.2.188.1 to 80.2.191.25480.2.191.2551,022
17780.2.192.0/2280.2.192.1 to 80.2.195.25480.2.195.2551,022
17880.2.196.0/2280.2.196.1 to 80.2.199.25480.2.199.2551,022
17980.2.200.0/2280.2.200.1 to 80.2.203.25480.2.203.2551,022
18080.2.204.0/2280.2.204.1 to 80.2.207.25480.2.207.2551,022
18180.2.208.0/2280.2.208.1 to 80.2.211.25480.2.211.2551,022
18280.2.212.0/2280.2.212.1 to 80.2.215.25480.2.215.2551,022
18380.2.216.0/2280.2.216.1 to 80.2.219.25480.2.219.2551,022
18480.2.220.0/2280.2.220.1 to 80.2.223.25480.2.223.2551,022
18580.2.224.0/2280.2.224.1 to 80.2.227.25480.2.227.2551,022
18680.2.228.0/2280.2.228.1 to 80.2.231.25480.2.231.2551,022
18780.2.232.0/2280.2.232.1 to 80.2.235.25480.2.235.2551,022
18880.2.236.0/2280.2.236.1 to 80.2.239.25480.2.239.2551,022
18980.2.240.0/2280.2.240.1 to 80.2.243.25480.2.243.2551,022
19080.2.244.0/2280.2.244.1 to 80.2.247.25480.2.247.2551,022
19180.2.248.0/2280.2.248.1 to 80.2.251.25480.2.251.2551,022
19280.2.252.0/2280.2.252.1 to 80.2.255.25480.2.255.2551,022
19380.3.0.0/2280.3.0.1 to 80.3.3.25480.3.3.2551,022
19480.3.4.0/2280.3.4.1 to 80.3.7.25480.3.7.2551,022
19580.3.8.0/2280.3.8.1 to 80.3.11.25480.3.11.2551,022
19680.3.12.0/2280.3.12.1 to 80.3.15.25480.3.15.2551,022
19780.3.16.0/2280.3.16.1 to 80.3.19.25480.3.19.2551,022
19880.3.20.0/2280.3.20.1 to 80.3.23.25480.3.23.2551,022
19980.3.24.0/2280.3.24.1 to 80.3.27.25480.3.27.2551,022
20080.3.28.0/2280.3.28.1 to 80.3.31.25480.3.31.2551,022
20180.3.32.0/2280.3.32.1 to 80.3.35.25480.3.35.2551,022
20280.3.36.0/2280.3.36.1 to 80.3.39.25480.3.39.2551,022
20380.3.40.0/2280.3.40.1 to 80.3.43.25480.3.43.2551,022
20480.3.44.0/2280.3.44.1 to 80.3.47.25480.3.47.2551,022
20580.3.48.0/2280.3.48.1 to 80.3.51.25480.3.51.2551,022
20680.3.52.0/2280.3.52.1 to 80.3.55.25480.3.55.2551,022
20780.3.56.0/2280.3.56.1 to 80.3.59.25480.3.59.2551,022
20880.3.60.0/2280.3.60.1 to 80.3.63.25480.3.63.2551,022
20980.3.64.0/2280.3.64.1 to 80.3.67.25480.3.67.2551,022
21080.3.68.0/2280.3.68.1 to 80.3.71.25480.3.71.2551,022
21180.3.72.0/2280.3.72.1 to 80.3.75.25480.3.75.2551,022
21280.3.76.0/2280.3.76.1 to 80.3.79.25480.3.79.2551,022
21380.3.80.0/2280.3.80.1 to 80.3.83.25480.3.83.2551,022
21480.3.84.0/2280.3.84.1 to 80.3.87.25480.3.87.2551,022
21580.3.88.0/2280.3.88.1 to 80.3.91.25480.3.91.2551,022
21680.3.92.0/2280.3.92.1 to 80.3.95.25480.3.95.2551,022
21780.3.96.0/2280.3.96.1 to 80.3.99.25480.3.99.2551,022
21880.3.100.0/2280.3.100.1 to 80.3.103.25480.3.103.2551,022
21980.3.104.0/2280.3.104.1 to 80.3.107.25480.3.107.2551,022
22080.3.108.0/2280.3.108.1 to 80.3.111.25480.3.111.2551,022
22180.3.112.0/2280.3.112.1 to 80.3.115.25480.3.115.2551,022
22280.3.116.0/2280.3.116.1 to 80.3.119.25480.3.119.2551,022
22380.3.120.0/2280.3.120.1 to 80.3.123.25480.3.123.2551,022
22480.3.124.0/2280.3.124.1 to 80.3.127.25480.3.127.2551,022
22580.3.128.0/2280.3.128.1 to 80.3.131.25480.3.131.2551,022
22680.3.132.0/2280.3.132.1 to 80.3.135.25480.3.135.2551,022
22780.3.136.0/2280.3.136.1 to 80.3.139.25480.3.139.2551,022
22880.3.140.0/2280.3.140.1 to 80.3.143.25480.3.143.2551,022
22980.3.144.0/2280.3.144.1 to 80.3.147.25480.3.147.2551,022
23080.3.148.0/2280.3.148.1 to 80.3.151.25480.3.151.2551,022
23180.3.152.0/2280.3.152.1 to 80.3.155.25480.3.155.2551,022
23280.3.156.0/2280.3.156.1 to 80.3.159.25480.3.159.2551,022
23380.3.160.0/2280.3.160.1 to 80.3.163.25480.3.163.2551,022
23480.3.164.0/2280.3.164.1 to 80.3.167.25480.3.167.2551,022
23580.3.168.0/2280.3.168.1 to 80.3.171.25480.3.171.2551,022
23680.3.172.0/2280.3.172.1 to 80.3.175.25480.3.175.2551,022
23780.3.176.0/2280.3.176.1 to 80.3.179.25480.3.179.2551,022
23880.3.180.0/2280.3.180.1 to 80.3.183.25480.3.183.2551,022
23980.3.184.0/2280.3.184.1 to 80.3.187.25480.3.187.2551,022
24080.3.188.0/2280.3.188.1 to 80.3.191.25480.3.191.2551,022
24180.3.192.0/2280.3.192.1 to 80.3.195.25480.3.195.2551,022
24280.3.196.0/2280.3.196.1 to 80.3.199.25480.3.199.2551,022
24380.3.200.0/2280.3.200.1 to 80.3.203.25480.3.203.2551,022
24480.3.204.0/2280.3.204.1 to 80.3.207.25480.3.207.2551,022
24580.3.208.0/2280.3.208.1 to 80.3.211.25480.3.211.2551,022
24680.3.212.0/2280.3.212.1 to 80.3.215.25480.3.215.2551,022
24780.3.216.0/2280.3.216.1 to 80.3.219.25480.3.219.2551,022
24880.3.220.0/2280.3.220.1 to 80.3.223.25480.3.223.2551,022
24980.3.224.0/2280.3.224.1 to 80.3.227.25480.3.227.2551,022
25080.3.228.0/2280.3.228.1 to 80.3.231.25480.3.231.2551,022
25180.3.232.0/2280.3.232.1 to 80.3.235.25480.3.235.2551,022
25280.3.236.0/2280.3.236.1 to 80.3.239.25480.3.239.2551,022
25380.3.240.0/2280.3.240.1 to 80.3.243.25480.3.243.2551,022
25480.3.244.0/2280.3.244.1 to 80.3.247.25480.3.247.2551,022
25580.3.248.0/2280.3.248.1 to 80.3.251.25480.3.251.2551,022
25680.3.252.0/2280.3.252.1 to 80.3.255.25480.3.255.2551,022

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.