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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.

Network75.84.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
75.84.0.0
Broadcast address
75.87.255.255
First usable
75.84.0.1
Last usable
75.87.255.254
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 4B540000 · Integer 1263796224 to 1264058367
Reverse DNS zones
84.75.in-addr.arpa
85.75.in-addr.arpa
86.75.in-addr.arpa
87.75.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
Address01001011.01010100.00000000.0000000075.84.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01001011.01010100.00000000.0000000075.84.0.0
Broadcast01001011.01010111.11111111.1111111175.87.255.255
Split into smaller subnets/23
/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)

75.84.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
175.84.0.0/2375.84.0.1 to 75.84.1.25475.84.1.255510
275.84.2.0/2375.84.2.1 to 75.84.3.25475.84.3.255510
375.84.4.0/2375.84.4.1 to 75.84.5.25475.84.5.255510
475.84.6.0/2375.84.6.1 to 75.84.7.25475.84.7.255510
575.84.8.0/2375.84.8.1 to 75.84.9.25475.84.9.255510
675.84.10.0/2375.84.10.1 to 75.84.11.25475.84.11.255510
775.84.12.0/2375.84.12.1 to 75.84.13.25475.84.13.255510
875.84.14.0/2375.84.14.1 to 75.84.15.25475.84.15.255510
975.84.16.0/2375.84.16.1 to 75.84.17.25475.84.17.255510
1075.84.18.0/2375.84.18.1 to 75.84.19.25475.84.19.255510
1175.84.20.0/2375.84.20.1 to 75.84.21.25475.84.21.255510
1275.84.22.0/2375.84.22.1 to 75.84.23.25475.84.23.255510
1375.84.24.0/2375.84.24.1 to 75.84.25.25475.84.25.255510
1475.84.26.0/2375.84.26.1 to 75.84.27.25475.84.27.255510
1575.84.28.0/2375.84.28.1 to 75.84.29.25475.84.29.255510
1675.84.30.0/2375.84.30.1 to 75.84.31.25475.84.31.255510
1775.84.32.0/2375.84.32.1 to 75.84.33.25475.84.33.255510
1875.84.34.0/2375.84.34.1 to 75.84.35.25475.84.35.255510
1975.84.36.0/2375.84.36.1 to 75.84.37.25475.84.37.255510
2075.84.38.0/2375.84.38.1 to 75.84.39.25475.84.39.255510
2175.84.40.0/2375.84.40.1 to 75.84.41.25475.84.41.255510
2275.84.42.0/2375.84.42.1 to 75.84.43.25475.84.43.255510
2375.84.44.0/2375.84.44.1 to 75.84.45.25475.84.45.255510
2475.84.46.0/2375.84.46.1 to 75.84.47.25475.84.47.255510
2575.84.48.0/2375.84.48.1 to 75.84.49.25475.84.49.255510
2675.84.50.0/2375.84.50.1 to 75.84.51.25475.84.51.255510
2775.84.52.0/2375.84.52.1 to 75.84.53.25475.84.53.255510
2875.84.54.0/2375.84.54.1 to 75.84.55.25475.84.55.255510
2975.84.56.0/2375.84.56.1 to 75.84.57.25475.84.57.255510
3075.84.58.0/2375.84.58.1 to 75.84.59.25475.84.59.255510
3175.84.60.0/2375.84.60.1 to 75.84.61.25475.84.61.255510
3275.84.62.0/2375.84.62.1 to 75.84.63.25475.84.63.255510
3375.84.64.0/2375.84.64.1 to 75.84.65.25475.84.65.255510
3475.84.66.0/2375.84.66.1 to 75.84.67.25475.84.67.255510
3575.84.68.0/2375.84.68.1 to 75.84.69.25475.84.69.255510
3675.84.70.0/2375.84.70.1 to 75.84.71.25475.84.71.255510
3775.84.72.0/2375.84.72.1 to 75.84.73.25475.84.73.255510
3875.84.74.0/2375.84.74.1 to 75.84.75.25475.84.75.255510
3975.84.76.0/2375.84.76.1 to 75.84.77.25475.84.77.255510
4075.84.78.0/2375.84.78.1 to 75.84.79.25475.84.79.255510
4175.84.80.0/2375.84.80.1 to 75.84.81.25475.84.81.255510
4275.84.82.0/2375.84.82.1 to 75.84.83.25475.84.83.255510
4375.84.84.0/2375.84.84.1 to 75.84.85.25475.84.85.255510
4475.84.86.0/2375.84.86.1 to 75.84.87.25475.84.87.255510
4575.84.88.0/2375.84.88.1 to 75.84.89.25475.84.89.255510
4675.84.90.0/2375.84.90.1 to 75.84.91.25475.84.91.255510
4775.84.92.0/2375.84.92.1 to 75.84.93.25475.84.93.255510
4875.84.94.0/2375.84.94.1 to 75.84.95.25475.84.95.255510
4975.84.96.0/2375.84.96.1 to 75.84.97.25475.84.97.255510
5075.84.98.0/2375.84.98.1 to 75.84.99.25475.84.99.255510
5175.84.100.0/2375.84.100.1 to 75.84.101.25475.84.101.255510
5275.84.102.0/2375.84.102.1 to 75.84.103.25475.84.103.255510
5375.84.104.0/2375.84.104.1 to 75.84.105.25475.84.105.255510
5475.84.106.0/2375.84.106.1 to 75.84.107.25475.84.107.255510
5575.84.108.0/2375.84.108.1 to 75.84.109.25475.84.109.255510
5675.84.110.0/2375.84.110.1 to 75.84.111.25475.84.111.255510
5775.84.112.0/2375.84.112.1 to 75.84.113.25475.84.113.255510
5875.84.114.0/2375.84.114.1 to 75.84.115.25475.84.115.255510
5975.84.116.0/2375.84.116.1 to 75.84.117.25475.84.117.255510
6075.84.118.0/2375.84.118.1 to 75.84.119.25475.84.119.255510
6175.84.120.0/2375.84.120.1 to 75.84.121.25475.84.121.255510
6275.84.122.0/2375.84.122.1 to 75.84.123.25475.84.123.255510
6375.84.124.0/2375.84.124.1 to 75.84.125.25475.84.125.255510
6475.84.126.0/2375.84.126.1 to 75.84.127.25475.84.127.255510
6575.84.128.0/2375.84.128.1 to 75.84.129.25475.84.129.255510
6675.84.130.0/2375.84.130.1 to 75.84.131.25475.84.131.255510
6775.84.132.0/2375.84.132.1 to 75.84.133.25475.84.133.255510
6875.84.134.0/2375.84.134.1 to 75.84.135.25475.84.135.255510
6975.84.136.0/2375.84.136.1 to 75.84.137.25475.84.137.255510
7075.84.138.0/2375.84.138.1 to 75.84.139.25475.84.139.255510
7175.84.140.0/2375.84.140.1 to 75.84.141.25475.84.141.255510
7275.84.142.0/2375.84.142.1 to 75.84.143.25475.84.143.255510
7375.84.144.0/2375.84.144.1 to 75.84.145.25475.84.145.255510
7475.84.146.0/2375.84.146.1 to 75.84.147.25475.84.147.255510
7575.84.148.0/2375.84.148.1 to 75.84.149.25475.84.149.255510
7675.84.150.0/2375.84.150.1 to 75.84.151.25475.84.151.255510
7775.84.152.0/2375.84.152.1 to 75.84.153.25475.84.153.255510
7875.84.154.0/2375.84.154.1 to 75.84.155.25475.84.155.255510
7975.84.156.0/2375.84.156.1 to 75.84.157.25475.84.157.255510
8075.84.158.0/2375.84.158.1 to 75.84.159.25475.84.159.255510
8175.84.160.0/2375.84.160.1 to 75.84.161.25475.84.161.255510
8275.84.162.0/2375.84.162.1 to 75.84.163.25475.84.163.255510
8375.84.164.0/2375.84.164.1 to 75.84.165.25475.84.165.255510
8475.84.166.0/2375.84.166.1 to 75.84.167.25475.84.167.255510
8575.84.168.0/2375.84.168.1 to 75.84.169.25475.84.169.255510
8675.84.170.0/2375.84.170.1 to 75.84.171.25475.84.171.255510
8775.84.172.0/2375.84.172.1 to 75.84.173.25475.84.173.255510
8875.84.174.0/2375.84.174.1 to 75.84.175.25475.84.175.255510
8975.84.176.0/2375.84.176.1 to 75.84.177.25475.84.177.255510
9075.84.178.0/2375.84.178.1 to 75.84.179.25475.84.179.255510
9175.84.180.0/2375.84.180.1 to 75.84.181.25475.84.181.255510
9275.84.182.0/2375.84.182.1 to 75.84.183.25475.84.183.255510
9375.84.184.0/2375.84.184.1 to 75.84.185.25475.84.185.255510
9475.84.186.0/2375.84.186.1 to 75.84.187.25475.84.187.255510
9575.84.188.0/2375.84.188.1 to 75.84.189.25475.84.189.255510
9675.84.190.0/2375.84.190.1 to 75.84.191.25475.84.191.255510
9775.84.192.0/2375.84.192.1 to 75.84.193.25475.84.193.255510
9875.84.194.0/2375.84.194.1 to 75.84.195.25475.84.195.255510
9975.84.196.0/2375.84.196.1 to 75.84.197.25475.84.197.255510
10075.84.198.0/2375.84.198.1 to 75.84.199.25475.84.199.255510
10175.84.200.0/2375.84.200.1 to 75.84.201.25475.84.201.255510
10275.84.202.0/2375.84.202.1 to 75.84.203.25475.84.203.255510
10375.84.204.0/2375.84.204.1 to 75.84.205.25475.84.205.255510
10475.84.206.0/2375.84.206.1 to 75.84.207.25475.84.207.255510
10575.84.208.0/2375.84.208.1 to 75.84.209.25475.84.209.255510
10675.84.210.0/2375.84.210.1 to 75.84.211.25475.84.211.255510
10775.84.212.0/2375.84.212.1 to 75.84.213.25475.84.213.255510
10875.84.214.0/2375.84.214.1 to 75.84.215.25475.84.215.255510
10975.84.216.0/2375.84.216.1 to 75.84.217.25475.84.217.255510
11075.84.218.0/2375.84.218.1 to 75.84.219.25475.84.219.255510
11175.84.220.0/2375.84.220.1 to 75.84.221.25475.84.221.255510
11275.84.222.0/2375.84.222.1 to 75.84.223.25475.84.223.255510
11375.84.224.0/2375.84.224.1 to 75.84.225.25475.84.225.255510
11475.84.226.0/2375.84.226.1 to 75.84.227.25475.84.227.255510
11575.84.228.0/2375.84.228.1 to 75.84.229.25475.84.229.255510
11675.84.230.0/2375.84.230.1 to 75.84.231.25475.84.231.255510
11775.84.232.0/2375.84.232.1 to 75.84.233.25475.84.233.255510
11875.84.234.0/2375.84.234.1 to 75.84.235.25475.84.235.255510
11975.84.236.0/2375.84.236.1 to 75.84.237.25475.84.237.255510
12075.84.238.0/2375.84.238.1 to 75.84.239.25475.84.239.255510
12175.84.240.0/2375.84.240.1 to 75.84.241.25475.84.241.255510
12275.84.242.0/2375.84.242.1 to 75.84.243.25475.84.243.255510
12375.84.244.0/2375.84.244.1 to 75.84.245.25475.84.245.255510
12475.84.246.0/2375.84.246.1 to 75.84.247.25475.84.247.255510
12575.84.248.0/2375.84.248.1 to 75.84.249.25475.84.249.255510
12675.84.250.0/2375.84.250.1 to 75.84.251.25475.84.251.255510
12775.84.252.0/2375.84.252.1 to 75.84.253.25475.84.253.255510
12875.84.254.0/2375.84.254.1 to 75.84.255.25475.84.255.255510
12975.85.0.0/2375.85.0.1 to 75.85.1.25475.85.1.255510
13075.85.2.0/2375.85.2.1 to 75.85.3.25475.85.3.255510
13175.85.4.0/2375.85.4.1 to 75.85.5.25475.85.5.255510
13275.85.6.0/2375.85.6.1 to 75.85.7.25475.85.7.255510
13375.85.8.0/2375.85.8.1 to 75.85.9.25475.85.9.255510
13475.85.10.0/2375.85.10.1 to 75.85.11.25475.85.11.255510
13575.85.12.0/2375.85.12.1 to 75.85.13.25475.85.13.255510
13675.85.14.0/2375.85.14.1 to 75.85.15.25475.85.15.255510
13775.85.16.0/2375.85.16.1 to 75.85.17.25475.85.17.255510
13875.85.18.0/2375.85.18.1 to 75.85.19.25475.85.19.255510
13975.85.20.0/2375.85.20.1 to 75.85.21.25475.85.21.255510
14075.85.22.0/2375.85.22.1 to 75.85.23.25475.85.23.255510
14175.85.24.0/2375.85.24.1 to 75.85.25.25475.85.25.255510
14275.85.26.0/2375.85.26.1 to 75.85.27.25475.85.27.255510
14375.85.28.0/2375.85.28.1 to 75.85.29.25475.85.29.255510
14475.85.30.0/2375.85.30.1 to 75.85.31.25475.85.31.255510
14575.85.32.0/2375.85.32.1 to 75.85.33.25475.85.33.255510
14675.85.34.0/2375.85.34.1 to 75.85.35.25475.85.35.255510
14775.85.36.0/2375.85.36.1 to 75.85.37.25475.85.37.255510
14875.85.38.0/2375.85.38.1 to 75.85.39.25475.85.39.255510
14975.85.40.0/2375.85.40.1 to 75.85.41.25475.85.41.255510
15075.85.42.0/2375.85.42.1 to 75.85.43.25475.85.43.255510
15175.85.44.0/2375.85.44.1 to 75.85.45.25475.85.45.255510
15275.85.46.0/2375.85.46.1 to 75.85.47.25475.85.47.255510
15375.85.48.0/2375.85.48.1 to 75.85.49.25475.85.49.255510
15475.85.50.0/2375.85.50.1 to 75.85.51.25475.85.51.255510
15575.85.52.0/2375.85.52.1 to 75.85.53.25475.85.53.255510
15675.85.54.0/2375.85.54.1 to 75.85.55.25475.85.55.255510
15775.85.56.0/2375.85.56.1 to 75.85.57.25475.85.57.255510
15875.85.58.0/2375.85.58.1 to 75.85.59.25475.85.59.255510
15975.85.60.0/2375.85.60.1 to 75.85.61.25475.85.61.255510
16075.85.62.0/2375.85.62.1 to 75.85.63.25475.85.63.255510
16175.85.64.0/2375.85.64.1 to 75.85.65.25475.85.65.255510
16275.85.66.0/2375.85.66.1 to 75.85.67.25475.85.67.255510
16375.85.68.0/2375.85.68.1 to 75.85.69.25475.85.69.255510
16475.85.70.0/2375.85.70.1 to 75.85.71.25475.85.71.255510
16575.85.72.0/2375.85.72.1 to 75.85.73.25475.85.73.255510
16675.85.74.0/2375.85.74.1 to 75.85.75.25475.85.75.255510
16775.85.76.0/2375.85.76.1 to 75.85.77.25475.85.77.255510
16875.85.78.0/2375.85.78.1 to 75.85.79.25475.85.79.255510
16975.85.80.0/2375.85.80.1 to 75.85.81.25475.85.81.255510
17075.85.82.0/2375.85.82.1 to 75.85.83.25475.85.83.255510
17175.85.84.0/2375.85.84.1 to 75.85.85.25475.85.85.255510
17275.85.86.0/2375.85.86.1 to 75.85.87.25475.85.87.255510
17375.85.88.0/2375.85.88.1 to 75.85.89.25475.85.89.255510
17475.85.90.0/2375.85.90.1 to 75.85.91.25475.85.91.255510
17575.85.92.0/2375.85.92.1 to 75.85.93.25475.85.93.255510
17675.85.94.0/2375.85.94.1 to 75.85.95.25475.85.95.255510
17775.85.96.0/2375.85.96.1 to 75.85.97.25475.85.97.255510
17875.85.98.0/2375.85.98.1 to 75.85.99.25475.85.99.255510
17975.85.100.0/2375.85.100.1 to 75.85.101.25475.85.101.255510
18075.85.102.0/2375.85.102.1 to 75.85.103.25475.85.103.255510
18175.85.104.0/2375.85.104.1 to 75.85.105.25475.85.105.255510
18275.85.106.0/2375.85.106.1 to 75.85.107.25475.85.107.255510
18375.85.108.0/2375.85.108.1 to 75.85.109.25475.85.109.255510
18475.85.110.0/2375.85.110.1 to 75.85.111.25475.85.111.255510
18575.85.112.0/2375.85.112.1 to 75.85.113.25475.85.113.255510
18675.85.114.0/2375.85.114.1 to 75.85.115.25475.85.115.255510
18775.85.116.0/2375.85.116.1 to 75.85.117.25475.85.117.255510
18875.85.118.0/2375.85.118.1 to 75.85.119.25475.85.119.255510
18975.85.120.0/2375.85.120.1 to 75.85.121.25475.85.121.255510
19075.85.122.0/2375.85.122.1 to 75.85.123.25475.85.123.255510
19175.85.124.0/2375.85.124.1 to 75.85.125.25475.85.125.255510
19275.85.126.0/2375.85.126.1 to 75.85.127.25475.85.127.255510
19375.85.128.0/2375.85.128.1 to 75.85.129.25475.85.129.255510
19475.85.130.0/2375.85.130.1 to 75.85.131.25475.85.131.255510
19575.85.132.0/2375.85.132.1 to 75.85.133.25475.85.133.255510
19675.85.134.0/2375.85.134.1 to 75.85.135.25475.85.135.255510
19775.85.136.0/2375.85.136.1 to 75.85.137.25475.85.137.255510
19875.85.138.0/2375.85.138.1 to 75.85.139.25475.85.139.255510
19975.85.140.0/2375.85.140.1 to 75.85.141.25475.85.141.255510
20075.85.142.0/2375.85.142.1 to 75.85.143.25475.85.143.255510
20175.85.144.0/2375.85.144.1 to 75.85.145.25475.85.145.255510
20275.85.146.0/2375.85.146.1 to 75.85.147.25475.85.147.255510
20375.85.148.0/2375.85.148.1 to 75.85.149.25475.85.149.255510
20475.85.150.0/2375.85.150.1 to 75.85.151.25475.85.151.255510
20575.85.152.0/2375.85.152.1 to 75.85.153.25475.85.153.255510
20675.85.154.0/2375.85.154.1 to 75.85.155.25475.85.155.255510
20775.85.156.0/2375.85.156.1 to 75.85.157.25475.85.157.255510
20875.85.158.0/2375.85.158.1 to 75.85.159.25475.85.159.255510
20975.85.160.0/2375.85.160.1 to 75.85.161.25475.85.161.255510
21075.85.162.0/2375.85.162.1 to 75.85.163.25475.85.163.255510
21175.85.164.0/2375.85.164.1 to 75.85.165.25475.85.165.255510
21275.85.166.0/2375.85.166.1 to 75.85.167.25475.85.167.255510
21375.85.168.0/2375.85.168.1 to 75.85.169.25475.85.169.255510
21475.85.170.0/2375.85.170.1 to 75.85.171.25475.85.171.255510
21575.85.172.0/2375.85.172.1 to 75.85.173.25475.85.173.255510
21675.85.174.0/2375.85.174.1 to 75.85.175.25475.85.175.255510
21775.85.176.0/2375.85.176.1 to 75.85.177.25475.85.177.255510
21875.85.178.0/2375.85.178.1 to 75.85.179.25475.85.179.255510
21975.85.180.0/2375.85.180.1 to 75.85.181.25475.85.181.255510
22075.85.182.0/2375.85.182.1 to 75.85.183.25475.85.183.255510
22175.85.184.0/2375.85.184.1 to 75.85.185.25475.85.185.255510
22275.85.186.0/2375.85.186.1 to 75.85.187.25475.85.187.255510
22375.85.188.0/2375.85.188.1 to 75.85.189.25475.85.189.255510
22475.85.190.0/2375.85.190.1 to 75.85.191.25475.85.191.255510
22575.85.192.0/2375.85.192.1 to 75.85.193.25475.85.193.255510
22675.85.194.0/2375.85.194.1 to 75.85.195.25475.85.195.255510
22775.85.196.0/2375.85.196.1 to 75.85.197.25475.85.197.255510
22875.85.198.0/2375.85.198.1 to 75.85.199.25475.85.199.255510
22975.85.200.0/2375.85.200.1 to 75.85.201.25475.85.201.255510
23075.85.202.0/2375.85.202.1 to 75.85.203.25475.85.203.255510
23175.85.204.0/2375.85.204.1 to 75.85.205.25475.85.205.255510
23275.85.206.0/2375.85.206.1 to 75.85.207.25475.85.207.255510
23375.85.208.0/2375.85.208.1 to 75.85.209.25475.85.209.255510
23475.85.210.0/2375.85.210.1 to 75.85.211.25475.85.211.255510
23575.85.212.0/2375.85.212.1 to 75.85.213.25475.85.213.255510
23675.85.214.0/2375.85.214.1 to 75.85.215.25475.85.215.255510
23775.85.216.0/2375.85.216.1 to 75.85.217.25475.85.217.255510
23875.85.218.0/2375.85.218.1 to 75.85.219.25475.85.219.255510
23975.85.220.0/2375.85.220.1 to 75.85.221.25475.85.221.255510
24075.85.222.0/2375.85.222.1 to 75.85.223.25475.85.223.255510
24175.85.224.0/2375.85.224.1 to 75.85.225.25475.85.225.255510
24275.85.226.0/2375.85.226.1 to 75.85.227.25475.85.227.255510
24375.85.228.0/2375.85.228.1 to 75.85.229.25475.85.229.255510
24475.85.230.0/2375.85.230.1 to 75.85.231.25475.85.231.255510
24575.85.232.0/2375.85.232.1 to 75.85.233.25475.85.233.255510
24675.85.234.0/2375.85.234.1 to 75.85.235.25475.85.235.255510
24775.85.236.0/2375.85.236.1 to 75.85.237.25475.85.237.255510
24875.85.238.0/2375.85.238.1 to 75.85.239.25475.85.239.255510
24975.85.240.0/2375.85.240.1 to 75.85.241.25475.85.241.255510
25075.85.242.0/2375.85.242.1 to 75.85.243.25475.85.243.255510
25175.85.244.0/2375.85.244.1 to 75.85.245.25475.85.245.255510
25275.85.246.0/2375.85.246.1 to 75.85.247.25475.85.247.255510
25375.85.248.0/2375.85.248.1 to 75.85.249.25475.85.249.255510
25475.85.250.0/2375.85.250.1 to 75.85.251.25475.85.251.255510
25575.85.252.0/2375.85.252.1 to 75.85.253.25475.85.253.255510
25675.85.254.0/2375.85.254.1 to 75.85.255.25475.85.255.255510

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.