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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.

Network64.80.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
64.80.0.0
Broadcast address
64.83.255.255
First usable
64.80.0.1
Last usable
64.83.255.254
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 40500000 · Integer 1078984704 to 1079246847
Reverse DNS zones
80.64.in-addr.arpa
81.64.in-addr.arpa
82.64.in-addr.arpa
83.64.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
Address01000000.01010000.00000000.0000000064.80.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01000000.01010000.00000000.0000000064.80.0.0
Broadcast01000000.01010011.11111111.1111111164.83.255.255
Split into smaller subnets/24
/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)

64.80.0.0/14 makes 1,024 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
164.80.0.0/2464.80.0.1 to 64.80.0.25464.80.0.255254
264.80.1.0/2464.80.1.1 to 64.80.1.25464.80.1.255254
364.80.2.0/2464.80.2.1 to 64.80.2.25464.80.2.255254
464.80.3.0/2464.80.3.1 to 64.80.3.25464.80.3.255254
564.80.4.0/2464.80.4.1 to 64.80.4.25464.80.4.255254
664.80.5.0/2464.80.5.1 to 64.80.5.25464.80.5.255254
764.80.6.0/2464.80.6.1 to 64.80.6.25464.80.6.255254
864.80.7.0/2464.80.7.1 to 64.80.7.25464.80.7.255254
964.80.8.0/2464.80.8.1 to 64.80.8.25464.80.8.255254
1064.80.9.0/2464.80.9.1 to 64.80.9.25464.80.9.255254
1164.80.10.0/2464.80.10.1 to 64.80.10.25464.80.10.255254
1264.80.11.0/2464.80.11.1 to 64.80.11.25464.80.11.255254
1364.80.12.0/2464.80.12.1 to 64.80.12.25464.80.12.255254
1464.80.13.0/2464.80.13.1 to 64.80.13.25464.80.13.255254
1564.80.14.0/2464.80.14.1 to 64.80.14.25464.80.14.255254
1664.80.15.0/2464.80.15.1 to 64.80.15.25464.80.15.255254
1764.80.16.0/2464.80.16.1 to 64.80.16.25464.80.16.255254
1864.80.17.0/2464.80.17.1 to 64.80.17.25464.80.17.255254
1964.80.18.0/2464.80.18.1 to 64.80.18.25464.80.18.255254
2064.80.19.0/2464.80.19.1 to 64.80.19.25464.80.19.255254
2164.80.20.0/2464.80.20.1 to 64.80.20.25464.80.20.255254
2264.80.21.0/2464.80.21.1 to 64.80.21.25464.80.21.255254
2364.80.22.0/2464.80.22.1 to 64.80.22.25464.80.22.255254
2464.80.23.0/2464.80.23.1 to 64.80.23.25464.80.23.255254
2564.80.24.0/2464.80.24.1 to 64.80.24.25464.80.24.255254
2664.80.25.0/2464.80.25.1 to 64.80.25.25464.80.25.255254
2764.80.26.0/2464.80.26.1 to 64.80.26.25464.80.26.255254
2864.80.27.0/2464.80.27.1 to 64.80.27.25464.80.27.255254
2964.80.28.0/2464.80.28.1 to 64.80.28.25464.80.28.255254
3064.80.29.0/2464.80.29.1 to 64.80.29.25464.80.29.255254
3164.80.30.0/2464.80.30.1 to 64.80.30.25464.80.30.255254
3264.80.31.0/2464.80.31.1 to 64.80.31.25464.80.31.255254
3364.80.32.0/2464.80.32.1 to 64.80.32.25464.80.32.255254
3464.80.33.0/2464.80.33.1 to 64.80.33.25464.80.33.255254
3564.80.34.0/2464.80.34.1 to 64.80.34.25464.80.34.255254
3664.80.35.0/2464.80.35.1 to 64.80.35.25464.80.35.255254
3764.80.36.0/2464.80.36.1 to 64.80.36.25464.80.36.255254
3864.80.37.0/2464.80.37.1 to 64.80.37.25464.80.37.255254
3964.80.38.0/2464.80.38.1 to 64.80.38.25464.80.38.255254
4064.80.39.0/2464.80.39.1 to 64.80.39.25464.80.39.255254
4164.80.40.0/2464.80.40.1 to 64.80.40.25464.80.40.255254
4264.80.41.0/2464.80.41.1 to 64.80.41.25464.80.41.255254
4364.80.42.0/2464.80.42.1 to 64.80.42.25464.80.42.255254
4464.80.43.0/2464.80.43.1 to 64.80.43.25464.80.43.255254
4564.80.44.0/2464.80.44.1 to 64.80.44.25464.80.44.255254
4664.80.45.0/2464.80.45.1 to 64.80.45.25464.80.45.255254
4764.80.46.0/2464.80.46.1 to 64.80.46.25464.80.46.255254
4864.80.47.0/2464.80.47.1 to 64.80.47.25464.80.47.255254
4964.80.48.0/2464.80.48.1 to 64.80.48.25464.80.48.255254
5064.80.49.0/2464.80.49.1 to 64.80.49.25464.80.49.255254
5164.80.50.0/2464.80.50.1 to 64.80.50.25464.80.50.255254
5264.80.51.0/2464.80.51.1 to 64.80.51.25464.80.51.255254
5364.80.52.0/2464.80.52.1 to 64.80.52.25464.80.52.255254
5464.80.53.0/2464.80.53.1 to 64.80.53.25464.80.53.255254
5564.80.54.0/2464.80.54.1 to 64.80.54.25464.80.54.255254
5664.80.55.0/2464.80.55.1 to 64.80.55.25464.80.55.255254
5764.80.56.0/2464.80.56.1 to 64.80.56.25464.80.56.255254
5864.80.57.0/2464.80.57.1 to 64.80.57.25464.80.57.255254
5964.80.58.0/2464.80.58.1 to 64.80.58.25464.80.58.255254
6064.80.59.0/2464.80.59.1 to 64.80.59.25464.80.59.255254
6164.80.60.0/2464.80.60.1 to 64.80.60.25464.80.60.255254
6264.80.61.0/2464.80.61.1 to 64.80.61.25464.80.61.255254
6364.80.62.0/2464.80.62.1 to 64.80.62.25464.80.62.255254
6464.80.63.0/2464.80.63.1 to 64.80.63.25464.80.63.255254
6564.80.64.0/2464.80.64.1 to 64.80.64.25464.80.64.255254
6664.80.65.0/2464.80.65.1 to 64.80.65.25464.80.65.255254
6764.80.66.0/2464.80.66.1 to 64.80.66.25464.80.66.255254
6864.80.67.0/2464.80.67.1 to 64.80.67.25464.80.67.255254
6964.80.68.0/2464.80.68.1 to 64.80.68.25464.80.68.255254
7064.80.69.0/2464.80.69.1 to 64.80.69.25464.80.69.255254
7164.80.70.0/2464.80.70.1 to 64.80.70.25464.80.70.255254
7264.80.71.0/2464.80.71.1 to 64.80.71.25464.80.71.255254
7364.80.72.0/2464.80.72.1 to 64.80.72.25464.80.72.255254
7464.80.73.0/2464.80.73.1 to 64.80.73.25464.80.73.255254
7564.80.74.0/2464.80.74.1 to 64.80.74.25464.80.74.255254
7664.80.75.0/2464.80.75.1 to 64.80.75.25464.80.75.255254
7764.80.76.0/2464.80.76.1 to 64.80.76.25464.80.76.255254
7864.80.77.0/2464.80.77.1 to 64.80.77.25464.80.77.255254
7964.80.78.0/2464.80.78.1 to 64.80.78.25464.80.78.255254
8064.80.79.0/2464.80.79.1 to 64.80.79.25464.80.79.255254
8164.80.80.0/2464.80.80.1 to 64.80.80.25464.80.80.255254
8264.80.81.0/2464.80.81.1 to 64.80.81.25464.80.81.255254
8364.80.82.0/2464.80.82.1 to 64.80.82.25464.80.82.255254
8464.80.83.0/2464.80.83.1 to 64.80.83.25464.80.83.255254
8564.80.84.0/2464.80.84.1 to 64.80.84.25464.80.84.255254
8664.80.85.0/2464.80.85.1 to 64.80.85.25464.80.85.255254
8764.80.86.0/2464.80.86.1 to 64.80.86.25464.80.86.255254
8864.80.87.0/2464.80.87.1 to 64.80.87.25464.80.87.255254
8964.80.88.0/2464.80.88.1 to 64.80.88.25464.80.88.255254
9064.80.89.0/2464.80.89.1 to 64.80.89.25464.80.89.255254
9164.80.90.0/2464.80.90.1 to 64.80.90.25464.80.90.255254
9264.80.91.0/2464.80.91.1 to 64.80.91.25464.80.91.255254
9364.80.92.0/2464.80.92.1 to 64.80.92.25464.80.92.255254
9464.80.93.0/2464.80.93.1 to 64.80.93.25464.80.93.255254
9564.80.94.0/2464.80.94.1 to 64.80.94.25464.80.94.255254
9664.80.95.0/2464.80.95.1 to 64.80.95.25464.80.95.255254
9764.80.96.0/2464.80.96.1 to 64.80.96.25464.80.96.255254
9864.80.97.0/2464.80.97.1 to 64.80.97.25464.80.97.255254
9964.80.98.0/2464.80.98.1 to 64.80.98.25464.80.98.255254
10064.80.99.0/2464.80.99.1 to 64.80.99.25464.80.99.255254
10164.80.100.0/2464.80.100.1 to 64.80.100.25464.80.100.255254
10264.80.101.0/2464.80.101.1 to 64.80.101.25464.80.101.255254
10364.80.102.0/2464.80.102.1 to 64.80.102.25464.80.102.255254
10464.80.103.0/2464.80.103.1 to 64.80.103.25464.80.103.255254
10564.80.104.0/2464.80.104.1 to 64.80.104.25464.80.104.255254
10664.80.105.0/2464.80.105.1 to 64.80.105.25464.80.105.255254
10764.80.106.0/2464.80.106.1 to 64.80.106.25464.80.106.255254
10864.80.107.0/2464.80.107.1 to 64.80.107.25464.80.107.255254
10964.80.108.0/2464.80.108.1 to 64.80.108.25464.80.108.255254
11064.80.109.0/2464.80.109.1 to 64.80.109.25464.80.109.255254
11164.80.110.0/2464.80.110.1 to 64.80.110.25464.80.110.255254
11264.80.111.0/2464.80.111.1 to 64.80.111.25464.80.111.255254
11364.80.112.0/2464.80.112.1 to 64.80.112.25464.80.112.255254
11464.80.113.0/2464.80.113.1 to 64.80.113.25464.80.113.255254
11564.80.114.0/2464.80.114.1 to 64.80.114.25464.80.114.255254
11664.80.115.0/2464.80.115.1 to 64.80.115.25464.80.115.255254
11764.80.116.0/2464.80.116.1 to 64.80.116.25464.80.116.255254
11864.80.117.0/2464.80.117.1 to 64.80.117.25464.80.117.255254
11964.80.118.0/2464.80.118.1 to 64.80.118.25464.80.118.255254
12064.80.119.0/2464.80.119.1 to 64.80.119.25464.80.119.255254
12164.80.120.0/2464.80.120.1 to 64.80.120.25464.80.120.255254
12264.80.121.0/2464.80.121.1 to 64.80.121.25464.80.121.255254
12364.80.122.0/2464.80.122.1 to 64.80.122.25464.80.122.255254
12464.80.123.0/2464.80.123.1 to 64.80.123.25464.80.123.255254
12564.80.124.0/2464.80.124.1 to 64.80.124.25464.80.124.255254
12664.80.125.0/2464.80.125.1 to 64.80.125.25464.80.125.255254
12764.80.126.0/2464.80.126.1 to 64.80.126.25464.80.126.255254
12864.80.127.0/2464.80.127.1 to 64.80.127.25464.80.127.255254
12964.80.128.0/2464.80.128.1 to 64.80.128.25464.80.128.255254
13064.80.129.0/2464.80.129.1 to 64.80.129.25464.80.129.255254
13164.80.130.0/2464.80.130.1 to 64.80.130.25464.80.130.255254
13264.80.131.0/2464.80.131.1 to 64.80.131.25464.80.131.255254
13364.80.132.0/2464.80.132.1 to 64.80.132.25464.80.132.255254
13464.80.133.0/2464.80.133.1 to 64.80.133.25464.80.133.255254
13564.80.134.0/2464.80.134.1 to 64.80.134.25464.80.134.255254
13664.80.135.0/2464.80.135.1 to 64.80.135.25464.80.135.255254
13764.80.136.0/2464.80.136.1 to 64.80.136.25464.80.136.255254
13864.80.137.0/2464.80.137.1 to 64.80.137.25464.80.137.255254
13964.80.138.0/2464.80.138.1 to 64.80.138.25464.80.138.255254
14064.80.139.0/2464.80.139.1 to 64.80.139.25464.80.139.255254
14164.80.140.0/2464.80.140.1 to 64.80.140.25464.80.140.255254
14264.80.141.0/2464.80.141.1 to 64.80.141.25464.80.141.255254
14364.80.142.0/2464.80.142.1 to 64.80.142.25464.80.142.255254
14464.80.143.0/2464.80.143.1 to 64.80.143.25464.80.143.255254
14564.80.144.0/2464.80.144.1 to 64.80.144.25464.80.144.255254
14664.80.145.0/2464.80.145.1 to 64.80.145.25464.80.145.255254
14764.80.146.0/2464.80.146.1 to 64.80.146.25464.80.146.255254
14864.80.147.0/2464.80.147.1 to 64.80.147.25464.80.147.255254
14964.80.148.0/2464.80.148.1 to 64.80.148.25464.80.148.255254
15064.80.149.0/2464.80.149.1 to 64.80.149.25464.80.149.255254
15164.80.150.0/2464.80.150.1 to 64.80.150.25464.80.150.255254
15264.80.151.0/2464.80.151.1 to 64.80.151.25464.80.151.255254
15364.80.152.0/2464.80.152.1 to 64.80.152.25464.80.152.255254
15464.80.153.0/2464.80.153.1 to 64.80.153.25464.80.153.255254
15564.80.154.0/2464.80.154.1 to 64.80.154.25464.80.154.255254
15664.80.155.0/2464.80.155.1 to 64.80.155.25464.80.155.255254
15764.80.156.0/2464.80.156.1 to 64.80.156.25464.80.156.255254
15864.80.157.0/2464.80.157.1 to 64.80.157.25464.80.157.255254
15964.80.158.0/2464.80.158.1 to 64.80.158.25464.80.158.255254
16064.80.159.0/2464.80.159.1 to 64.80.159.25464.80.159.255254
16164.80.160.0/2464.80.160.1 to 64.80.160.25464.80.160.255254
16264.80.161.0/2464.80.161.1 to 64.80.161.25464.80.161.255254
16364.80.162.0/2464.80.162.1 to 64.80.162.25464.80.162.255254
16464.80.163.0/2464.80.163.1 to 64.80.163.25464.80.163.255254
16564.80.164.0/2464.80.164.1 to 64.80.164.25464.80.164.255254
16664.80.165.0/2464.80.165.1 to 64.80.165.25464.80.165.255254
16764.80.166.0/2464.80.166.1 to 64.80.166.25464.80.166.255254
16864.80.167.0/2464.80.167.1 to 64.80.167.25464.80.167.255254
16964.80.168.0/2464.80.168.1 to 64.80.168.25464.80.168.255254
17064.80.169.0/2464.80.169.1 to 64.80.169.25464.80.169.255254
17164.80.170.0/2464.80.170.1 to 64.80.170.25464.80.170.255254
17264.80.171.0/2464.80.171.1 to 64.80.171.25464.80.171.255254
17364.80.172.0/2464.80.172.1 to 64.80.172.25464.80.172.255254
17464.80.173.0/2464.80.173.1 to 64.80.173.25464.80.173.255254
17564.80.174.0/2464.80.174.1 to 64.80.174.25464.80.174.255254
17664.80.175.0/2464.80.175.1 to 64.80.175.25464.80.175.255254
17764.80.176.0/2464.80.176.1 to 64.80.176.25464.80.176.255254
17864.80.177.0/2464.80.177.1 to 64.80.177.25464.80.177.255254
17964.80.178.0/2464.80.178.1 to 64.80.178.25464.80.178.255254
18064.80.179.0/2464.80.179.1 to 64.80.179.25464.80.179.255254
18164.80.180.0/2464.80.180.1 to 64.80.180.25464.80.180.255254
18264.80.181.0/2464.80.181.1 to 64.80.181.25464.80.181.255254
18364.80.182.0/2464.80.182.1 to 64.80.182.25464.80.182.255254
18464.80.183.0/2464.80.183.1 to 64.80.183.25464.80.183.255254
18564.80.184.0/2464.80.184.1 to 64.80.184.25464.80.184.255254
18664.80.185.0/2464.80.185.1 to 64.80.185.25464.80.185.255254
18764.80.186.0/2464.80.186.1 to 64.80.186.25464.80.186.255254
18864.80.187.0/2464.80.187.1 to 64.80.187.25464.80.187.255254
18964.80.188.0/2464.80.188.1 to 64.80.188.25464.80.188.255254
19064.80.189.0/2464.80.189.1 to 64.80.189.25464.80.189.255254
19164.80.190.0/2464.80.190.1 to 64.80.190.25464.80.190.255254
19264.80.191.0/2464.80.191.1 to 64.80.191.25464.80.191.255254
19364.80.192.0/2464.80.192.1 to 64.80.192.25464.80.192.255254
19464.80.193.0/2464.80.193.1 to 64.80.193.25464.80.193.255254
19564.80.194.0/2464.80.194.1 to 64.80.194.25464.80.194.255254
19664.80.195.0/2464.80.195.1 to 64.80.195.25464.80.195.255254
19764.80.196.0/2464.80.196.1 to 64.80.196.25464.80.196.255254
19864.80.197.0/2464.80.197.1 to 64.80.197.25464.80.197.255254
19964.80.198.0/2464.80.198.1 to 64.80.198.25464.80.198.255254
20064.80.199.0/2464.80.199.1 to 64.80.199.25464.80.199.255254
20164.80.200.0/2464.80.200.1 to 64.80.200.25464.80.200.255254
20264.80.201.0/2464.80.201.1 to 64.80.201.25464.80.201.255254
20364.80.202.0/2464.80.202.1 to 64.80.202.25464.80.202.255254
20464.80.203.0/2464.80.203.1 to 64.80.203.25464.80.203.255254
20564.80.204.0/2464.80.204.1 to 64.80.204.25464.80.204.255254
20664.80.205.0/2464.80.205.1 to 64.80.205.25464.80.205.255254
20764.80.206.0/2464.80.206.1 to 64.80.206.25464.80.206.255254
20864.80.207.0/2464.80.207.1 to 64.80.207.25464.80.207.255254
20964.80.208.0/2464.80.208.1 to 64.80.208.25464.80.208.255254
21064.80.209.0/2464.80.209.1 to 64.80.209.25464.80.209.255254
21164.80.210.0/2464.80.210.1 to 64.80.210.25464.80.210.255254
21264.80.211.0/2464.80.211.1 to 64.80.211.25464.80.211.255254
21364.80.212.0/2464.80.212.1 to 64.80.212.25464.80.212.255254
21464.80.213.0/2464.80.213.1 to 64.80.213.25464.80.213.255254
21564.80.214.0/2464.80.214.1 to 64.80.214.25464.80.214.255254
21664.80.215.0/2464.80.215.1 to 64.80.215.25464.80.215.255254
21764.80.216.0/2464.80.216.1 to 64.80.216.25464.80.216.255254
21864.80.217.0/2464.80.217.1 to 64.80.217.25464.80.217.255254
21964.80.218.0/2464.80.218.1 to 64.80.218.25464.80.218.255254
22064.80.219.0/2464.80.219.1 to 64.80.219.25464.80.219.255254
22164.80.220.0/2464.80.220.1 to 64.80.220.25464.80.220.255254
22264.80.221.0/2464.80.221.1 to 64.80.221.25464.80.221.255254
22364.80.222.0/2464.80.222.1 to 64.80.222.25464.80.222.255254
22464.80.223.0/2464.80.223.1 to 64.80.223.25464.80.223.255254
22564.80.224.0/2464.80.224.1 to 64.80.224.25464.80.224.255254
22664.80.225.0/2464.80.225.1 to 64.80.225.25464.80.225.255254
22764.80.226.0/2464.80.226.1 to 64.80.226.25464.80.226.255254
22864.80.227.0/2464.80.227.1 to 64.80.227.25464.80.227.255254
22964.80.228.0/2464.80.228.1 to 64.80.228.25464.80.228.255254
23064.80.229.0/2464.80.229.1 to 64.80.229.25464.80.229.255254
23164.80.230.0/2464.80.230.1 to 64.80.230.25464.80.230.255254
23264.80.231.0/2464.80.231.1 to 64.80.231.25464.80.231.255254
23364.80.232.0/2464.80.232.1 to 64.80.232.25464.80.232.255254
23464.80.233.0/2464.80.233.1 to 64.80.233.25464.80.233.255254
23564.80.234.0/2464.80.234.1 to 64.80.234.25464.80.234.255254
23664.80.235.0/2464.80.235.1 to 64.80.235.25464.80.235.255254
23764.80.236.0/2464.80.236.1 to 64.80.236.25464.80.236.255254
23864.80.237.0/2464.80.237.1 to 64.80.237.25464.80.237.255254
23964.80.238.0/2464.80.238.1 to 64.80.238.25464.80.238.255254
24064.80.239.0/2464.80.239.1 to 64.80.239.25464.80.239.255254
24164.80.240.0/2464.80.240.1 to 64.80.240.25464.80.240.255254
24264.80.241.0/2464.80.241.1 to 64.80.241.25464.80.241.255254
24364.80.242.0/2464.80.242.1 to 64.80.242.25464.80.242.255254
24464.80.243.0/2464.80.243.1 to 64.80.243.25464.80.243.255254
24564.80.244.0/2464.80.244.1 to 64.80.244.25464.80.244.255254
24664.80.245.0/2464.80.245.1 to 64.80.245.25464.80.245.255254
24764.80.246.0/2464.80.246.1 to 64.80.246.25464.80.246.255254
24864.80.247.0/2464.80.247.1 to 64.80.247.25464.80.247.255254
24964.80.248.0/2464.80.248.1 to 64.80.248.25464.80.248.255254
25064.80.249.0/2464.80.249.1 to 64.80.249.25464.80.249.255254
25164.80.250.0/2464.80.250.1 to 64.80.250.25464.80.250.255254
25264.80.251.0/2464.80.251.1 to 64.80.251.25464.80.251.255254
25364.80.252.0/2464.80.252.1 to 64.80.252.25464.80.252.255254
25464.80.253.0/2464.80.253.1 to 64.80.253.25464.80.253.255254
25564.80.254.0/2464.80.254.1 to 64.80.254.25464.80.254.255254
25664.80.255.0/2464.80.255.1 to 64.80.255.25464.80.255.255254

IPv4 CIDR reference (/0 to /32)

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

IPv6 prefix reference

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

Private and special ranges

IPv4

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

IPv6

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

About this tool

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

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

Common questions

Why are two addresses lost in every IPv4 subnet?

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

What size of IPv6 network should a LAN use?

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

What is a wildcard mask?

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

Which ranges can I use inside an office?

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