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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.

Network38.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
38.76.0.0
Broadcast address
38.79.255.255
First usable
38.76.0.1
Last usable
38.79.255.254
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 264C0000 · Integer 642514944 to 642777087
Reverse DNS zones
76.38.in-addr.arpa
77.38.in-addr.arpa
78.38.in-addr.arpa
79.38.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
Address00100110.01001100.00000000.0000000038.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00100110.01001100.00000000.0000000038.76.0.0
Broadcast00100110.01001111.11111111.1111111138.79.255.255
Split into smaller subnets/23

38.76.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
138.76.0.0/2338.76.0.1 to 38.76.1.25438.76.1.255510
238.76.2.0/2338.76.2.1 to 38.76.3.25438.76.3.255510
338.76.4.0/2338.76.4.1 to 38.76.5.25438.76.5.255510
438.76.6.0/2338.76.6.1 to 38.76.7.25438.76.7.255510
538.76.8.0/2338.76.8.1 to 38.76.9.25438.76.9.255510
638.76.10.0/2338.76.10.1 to 38.76.11.25438.76.11.255510
738.76.12.0/2338.76.12.1 to 38.76.13.25438.76.13.255510
838.76.14.0/2338.76.14.1 to 38.76.15.25438.76.15.255510
938.76.16.0/2338.76.16.1 to 38.76.17.25438.76.17.255510
1038.76.18.0/2338.76.18.1 to 38.76.19.25438.76.19.255510
1138.76.20.0/2338.76.20.1 to 38.76.21.25438.76.21.255510
1238.76.22.0/2338.76.22.1 to 38.76.23.25438.76.23.255510
1338.76.24.0/2338.76.24.1 to 38.76.25.25438.76.25.255510
1438.76.26.0/2338.76.26.1 to 38.76.27.25438.76.27.255510
1538.76.28.0/2338.76.28.1 to 38.76.29.25438.76.29.255510
1638.76.30.0/2338.76.30.1 to 38.76.31.25438.76.31.255510
1738.76.32.0/2338.76.32.1 to 38.76.33.25438.76.33.255510
1838.76.34.0/2338.76.34.1 to 38.76.35.25438.76.35.255510
1938.76.36.0/2338.76.36.1 to 38.76.37.25438.76.37.255510
2038.76.38.0/2338.76.38.1 to 38.76.39.25438.76.39.255510
2138.76.40.0/2338.76.40.1 to 38.76.41.25438.76.41.255510
2238.76.42.0/2338.76.42.1 to 38.76.43.25438.76.43.255510
2338.76.44.0/2338.76.44.1 to 38.76.45.25438.76.45.255510
2438.76.46.0/2338.76.46.1 to 38.76.47.25438.76.47.255510
2538.76.48.0/2338.76.48.1 to 38.76.49.25438.76.49.255510
2638.76.50.0/2338.76.50.1 to 38.76.51.25438.76.51.255510
2738.76.52.0/2338.76.52.1 to 38.76.53.25438.76.53.255510
2838.76.54.0/2338.76.54.1 to 38.76.55.25438.76.55.255510
2938.76.56.0/2338.76.56.1 to 38.76.57.25438.76.57.255510
3038.76.58.0/2338.76.58.1 to 38.76.59.25438.76.59.255510
3138.76.60.0/2338.76.60.1 to 38.76.61.25438.76.61.255510
3238.76.62.0/2338.76.62.1 to 38.76.63.25438.76.63.255510
3338.76.64.0/2338.76.64.1 to 38.76.65.25438.76.65.255510
3438.76.66.0/2338.76.66.1 to 38.76.67.25438.76.67.255510
3538.76.68.0/2338.76.68.1 to 38.76.69.25438.76.69.255510
3638.76.70.0/2338.76.70.1 to 38.76.71.25438.76.71.255510
3738.76.72.0/2338.76.72.1 to 38.76.73.25438.76.73.255510
3838.76.74.0/2338.76.74.1 to 38.76.75.25438.76.75.255510
3938.76.76.0/2338.76.76.1 to 38.76.77.25438.76.77.255510
4038.76.78.0/2338.76.78.1 to 38.76.79.25438.76.79.255510
4138.76.80.0/2338.76.80.1 to 38.76.81.25438.76.81.255510
4238.76.82.0/2338.76.82.1 to 38.76.83.25438.76.83.255510
4338.76.84.0/2338.76.84.1 to 38.76.85.25438.76.85.255510
4438.76.86.0/2338.76.86.1 to 38.76.87.25438.76.87.255510
4538.76.88.0/2338.76.88.1 to 38.76.89.25438.76.89.255510
4638.76.90.0/2338.76.90.1 to 38.76.91.25438.76.91.255510
4738.76.92.0/2338.76.92.1 to 38.76.93.25438.76.93.255510
4838.76.94.0/2338.76.94.1 to 38.76.95.25438.76.95.255510
4938.76.96.0/2338.76.96.1 to 38.76.97.25438.76.97.255510
5038.76.98.0/2338.76.98.1 to 38.76.99.25438.76.99.255510
5138.76.100.0/2338.76.100.1 to 38.76.101.25438.76.101.255510
5238.76.102.0/2338.76.102.1 to 38.76.103.25438.76.103.255510
5338.76.104.0/2338.76.104.1 to 38.76.105.25438.76.105.255510
5438.76.106.0/2338.76.106.1 to 38.76.107.25438.76.107.255510
5538.76.108.0/2338.76.108.1 to 38.76.109.25438.76.109.255510
5638.76.110.0/2338.76.110.1 to 38.76.111.25438.76.111.255510
5738.76.112.0/2338.76.112.1 to 38.76.113.25438.76.113.255510
5838.76.114.0/2338.76.114.1 to 38.76.115.25438.76.115.255510
5938.76.116.0/2338.76.116.1 to 38.76.117.25438.76.117.255510
6038.76.118.0/2338.76.118.1 to 38.76.119.25438.76.119.255510
6138.76.120.0/2338.76.120.1 to 38.76.121.25438.76.121.255510
6238.76.122.0/2338.76.122.1 to 38.76.123.25438.76.123.255510
6338.76.124.0/2338.76.124.1 to 38.76.125.25438.76.125.255510
6438.76.126.0/2338.76.126.1 to 38.76.127.25438.76.127.255510
6538.76.128.0/2338.76.128.1 to 38.76.129.25438.76.129.255510
6638.76.130.0/2338.76.130.1 to 38.76.131.25438.76.131.255510
6738.76.132.0/2338.76.132.1 to 38.76.133.25438.76.133.255510
6838.76.134.0/2338.76.134.1 to 38.76.135.25438.76.135.255510
6938.76.136.0/2338.76.136.1 to 38.76.137.25438.76.137.255510
7038.76.138.0/2338.76.138.1 to 38.76.139.25438.76.139.255510
7138.76.140.0/2338.76.140.1 to 38.76.141.25438.76.141.255510
7238.76.142.0/2338.76.142.1 to 38.76.143.25438.76.143.255510
7338.76.144.0/2338.76.144.1 to 38.76.145.25438.76.145.255510
7438.76.146.0/2338.76.146.1 to 38.76.147.25438.76.147.255510
7538.76.148.0/2338.76.148.1 to 38.76.149.25438.76.149.255510
7638.76.150.0/2338.76.150.1 to 38.76.151.25438.76.151.255510
7738.76.152.0/2338.76.152.1 to 38.76.153.25438.76.153.255510
7838.76.154.0/2338.76.154.1 to 38.76.155.25438.76.155.255510
7938.76.156.0/2338.76.156.1 to 38.76.157.25438.76.157.255510
8038.76.158.0/2338.76.158.1 to 38.76.159.25438.76.159.255510
8138.76.160.0/2338.76.160.1 to 38.76.161.25438.76.161.255510
8238.76.162.0/2338.76.162.1 to 38.76.163.25438.76.163.255510
8338.76.164.0/2338.76.164.1 to 38.76.165.25438.76.165.255510
8438.76.166.0/2338.76.166.1 to 38.76.167.25438.76.167.255510
8538.76.168.0/2338.76.168.1 to 38.76.169.25438.76.169.255510
8638.76.170.0/2338.76.170.1 to 38.76.171.25438.76.171.255510
8738.76.172.0/2338.76.172.1 to 38.76.173.25438.76.173.255510
8838.76.174.0/2338.76.174.1 to 38.76.175.25438.76.175.255510
8938.76.176.0/2338.76.176.1 to 38.76.177.25438.76.177.255510
9038.76.178.0/2338.76.178.1 to 38.76.179.25438.76.179.255510
9138.76.180.0/2338.76.180.1 to 38.76.181.25438.76.181.255510
9238.76.182.0/2338.76.182.1 to 38.76.183.25438.76.183.255510
9338.76.184.0/2338.76.184.1 to 38.76.185.25438.76.185.255510
9438.76.186.0/2338.76.186.1 to 38.76.187.25438.76.187.255510
9538.76.188.0/2338.76.188.1 to 38.76.189.25438.76.189.255510
9638.76.190.0/2338.76.190.1 to 38.76.191.25438.76.191.255510
9738.76.192.0/2338.76.192.1 to 38.76.193.25438.76.193.255510
9838.76.194.0/2338.76.194.1 to 38.76.195.25438.76.195.255510
9938.76.196.0/2338.76.196.1 to 38.76.197.25438.76.197.255510
10038.76.198.0/2338.76.198.1 to 38.76.199.25438.76.199.255510
10138.76.200.0/2338.76.200.1 to 38.76.201.25438.76.201.255510
10238.76.202.0/2338.76.202.1 to 38.76.203.25438.76.203.255510
10338.76.204.0/2338.76.204.1 to 38.76.205.25438.76.205.255510
10438.76.206.0/2338.76.206.1 to 38.76.207.25438.76.207.255510
10538.76.208.0/2338.76.208.1 to 38.76.209.25438.76.209.255510
10638.76.210.0/2338.76.210.1 to 38.76.211.25438.76.211.255510
10738.76.212.0/2338.76.212.1 to 38.76.213.25438.76.213.255510
10838.76.214.0/2338.76.214.1 to 38.76.215.25438.76.215.255510
10938.76.216.0/2338.76.216.1 to 38.76.217.25438.76.217.255510
11038.76.218.0/2338.76.218.1 to 38.76.219.25438.76.219.255510
11138.76.220.0/2338.76.220.1 to 38.76.221.25438.76.221.255510
11238.76.222.0/2338.76.222.1 to 38.76.223.25438.76.223.255510
11338.76.224.0/2338.76.224.1 to 38.76.225.25438.76.225.255510
11438.76.226.0/2338.76.226.1 to 38.76.227.25438.76.227.255510
11538.76.228.0/2338.76.228.1 to 38.76.229.25438.76.229.255510
11638.76.230.0/2338.76.230.1 to 38.76.231.25438.76.231.255510
11738.76.232.0/2338.76.232.1 to 38.76.233.25438.76.233.255510
11838.76.234.0/2338.76.234.1 to 38.76.235.25438.76.235.255510
11938.76.236.0/2338.76.236.1 to 38.76.237.25438.76.237.255510
12038.76.238.0/2338.76.238.1 to 38.76.239.25438.76.239.255510
12138.76.240.0/2338.76.240.1 to 38.76.241.25438.76.241.255510
12238.76.242.0/2338.76.242.1 to 38.76.243.25438.76.243.255510
12338.76.244.0/2338.76.244.1 to 38.76.245.25438.76.245.255510
12438.76.246.0/2338.76.246.1 to 38.76.247.25438.76.247.255510
12538.76.248.0/2338.76.248.1 to 38.76.249.25438.76.249.255510
12638.76.250.0/2338.76.250.1 to 38.76.251.25438.76.251.255510
12738.76.252.0/2338.76.252.1 to 38.76.253.25438.76.253.255510
12838.76.254.0/2338.76.254.1 to 38.76.255.25438.76.255.255510
12938.77.0.0/2338.77.0.1 to 38.77.1.25438.77.1.255510
13038.77.2.0/2338.77.2.1 to 38.77.3.25438.77.3.255510
13138.77.4.0/2338.77.4.1 to 38.77.5.25438.77.5.255510
13238.77.6.0/2338.77.6.1 to 38.77.7.25438.77.7.255510
13338.77.8.0/2338.77.8.1 to 38.77.9.25438.77.9.255510
13438.77.10.0/2338.77.10.1 to 38.77.11.25438.77.11.255510
13538.77.12.0/2338.77.12.1 to 38.77.13.25438.77.13.255510
13638.77.14.0/2338.77.14.1 to 38.77.15.25438.77.15.255510
13738.77.16.0/2338.77.16.1 to 38.77.17.25438.77.17.255510
13838.77.18.0/2338.77.18.1 to 38.77.19.25438.77.19.255510
13938.77.20.0/2338.77.20.1 to 38.77.21.25438.77.21.255510
14038.77.22.0/2338.77.22.1 to 38.77.23.25438.77.23.255510
14138.77.24.0/2338.77.24.1 to 38.77.25.25438.77.25.255510
14238.77.26.0/2338.77.26.1 to 38.77.27.25438.77.27.255510
14338.77.28.0/2338.77.28.1 to 38.77.29.25438.77.29.255510
14438.77.30.0/2338.77.30.1 to 38.77.31.25438.77.31.255510
14538.77.32.0/2338.77.32.1 to 38.77.33.25438.77.33.255510
14638.77.34.0/2338.77.34.1 to 38.77.35.25438.77.35.255510
14738.77.36.0/2338.77.36.1 to 38.77.37.25438.77.37.255510
14838.77.38.0/2338.77.38.1 to 38.77.39.25438.77.39.255510
14938.77.40.0/2338.77.40.1 to 38.77.41.25438.77.41.255510
15038.77.42.0/2338.77.42.1 to 38.77.43.25438.77.43.255510
15138.77.44.0/2338.77.44.1 to 38.77.45.25438.77.45.255510
15238.77.46.0/2338.77.46.1 to 38.77.47.25438.77.47.255510
15338.77.48.0/2338.77.48.1 to 38.77.49.25438.77.49.255510
15438.77.50.0/2338.77.50.1 to 38.77.51.25438.77.51.255510
15538.77.52.0/2338.77.52.1 to 38.77.53.25438.77.53.255510
15638.77.54.0/2338.77.54.1 to 38.77.55.25438.77.55.255510
15738.77.56.0/2338.77.56.1 to 38.77.57.25438.77.57.255510
15838.77.58.0/2338.77.58.1 to 38.77.59.25438.77.59.255510
15938.77.60.0/2338.77.60.1 to 38.77.61.25438.77.61.255510
16038.77.62.0/2338.77.62.1 to 38.77.63.25438.77.63.255510
16138.77.64.0/2338.77.64.1 to 38.77.65.25438.77.65.255510
16238.77.66.0/2338.77.66.1 to 38.77.67.25438.77.67.255510
16338.77.68.0/2338.77.68.1 to 38.77.69.25438.77.69.255510
16438.77.70.0/2338.77.70.1 to 38.77.71.25438.77.71.255510
16538.77.72.0/2338.77.72.1 to 38.77.73.25438.77.73.255510
16638.77.74.0/2338.77.74.1 to 38.77.75.25438.77.75.255510
16738.77.76.0/2338.77.76.1 to 38.77.77.25438.77.77.255510
16838.77.78.0/2338.77.78.1 to 38.77.79.25438.77.79.255510
16938.77.80.0/2338.77.80.1 to 38.77.81.25438.77.81.255510
17038.77.82.0/2338.77.82.1 to 38.77.83.25438.77.83.255510
17138.77.84.0/2338.77.84.1 to 38.77.85.25438.77.85.255510
17238.77.86.0/2338.77.86.1 to 38.77.87.25438.77.87.255510
17338.77.88.0/2338.77.88.1 to 38.77.89.25438.77.89.255510
17438.77.90.0/2338.77.90.1 to 38.77.91.25438.77.91.255510
17538.77.92.0/2338.77.92.1 to 38.77.93.25438.77.93.255510
17638.77.94.0/2338.77.94.1 to 38.77.95.25438.77.95.255510
17738.77.96.0/2338.77.96.1 to 38.77.97.25438.77.97.255510
17838.77.98.0/2338.77.98.1 to 38.77.99.25438.77.99.255510
17938.77.100.0/2338.77.100.1 to 38.77.101.25438.77.101.255510
18038.77.102.0/2338.77.102.1 to 38.77.103.25438.77.103.255510
18138.77.104.0/2338.77.104.1 to 38.77.105.25438.77.105.255510
18238.77.106.0/2338.77.106.1 to 38.77.107.25438.77.107.255510
18338.77.108.0/2338.77.108.1 to 38.77.109.25438.77.109.255510
18438.77.110.0/2338.77.110.1 to 38.77.111.25438.77.111.255510
18538.77.112.0/2338.77.112.1 to 38.77.113.25438.77.113.255510
18638.77.114.0/2338.77.114.1 to 38.77.115.25438.77.115.255510
18738.77.116.0/2338.77.116.1 to 38.77.117.25438.77.117.255510
18838.77.118.0/2338.77.118.1 to 38.77.119.25438.77.119.255510
18938.77.120.0/2338.77.120.1 to 38.77.121.25438.77.121.255510
19038.77.122.0/2338.77.122.1 to 38.77.123.25438.77.123.255510
19138.77.124.0/2338.77.124.1 to 38.77.125.25438.77.125.255510
19238.77.126.0/2338.77.126.1 to 38.77.127.25438.77.127.255510
19338.77.128.0/2338.77.128.1 to 38.77.129.25438.77.129.255510
19438.77.130.0/2338.77.130.1 to 38.77.131.25438.77.131.255510
19538.77.132.0/2338.77.132.1 to 38.77.133.25438.77.133.255510
19638.77.134.0/2338.77.134.1 to 38.77.135.25438.77.135.255510
19738.77.136.0/2338.77.136.1 to 38.77.137.25438.77.137.255510
19838.77.138.0/2338.77.138.1 to 38.77.139.25438.77.139.255510
19938.77.140.0/2338.77.140.1 to 38.77.141.25438.77.141.255510
20038.77.142.0/2338.77.142.1 to 38.77.143.25438.77.143.255510
20138.77.144.0/2338.77.144.1 to 38.77.145.25438.77.145.255510
20238.77.146.0/2338.77.146.1 to 38.77.147.25438.77.147.255510
20338.77.148.0/2338.77.148.1 to 38.77.149.25438.77.149.255510
20438.77.150.0/2338.77.150.1 to 38.77.151.25438.77.151.255510
20538.77.152.0/2338.77.152.1 to 38.77.153.25438.77.153.255510
20638.77.154.0/2338.77.154.1 to 38.77.155.25438.77.155.255510
20738.77.156.0/2338.77.156.1 to 38.77.157.25438.77.157.255510
20838.77.158.0/2338.77.158.1 to 38.77.159.25438.77.159.255510
20938.77.160.0/2338.77.160.1 to 38.77.161.25438.77.161.255510
21038.77.162.0/2338.77.162.1 to 38.77.163.25438.77.163.255510
21138.77.164.0/2338.77.164.1 to 38.77.165.25438.77.165.255510
21238.77.166.0/2338.77.166.1 to 38.77.167.25438.77.167.255510
21338.77.168.0/2338.77.168.1 to 38.77.169.25438.77.169.255510
21438.77.170.0/2338.77.170.1 to 38.77.171.25438.77.171.255510
21538.77.172.0/2338.77.172.1 to 38.77.173.25438.77.173.255510
21638.77.174.0/2338.77.174.1 to 38.77.175.25438.77.175.255510
21738.77.176.0/2338.77.176.1 to 38.77.177.25438.77.177.255510
21838.77.178.0/2338.77.178.1 to 38.77.179.25438.77.179.255510
21938.77.180.0/2338.77.180.1 to 38.77.181.25438.77.181.255510
22038.77.182.0/2338.77.182.1 to 38.77.183.25438.77.183.255510
22138.77.184.0/2338.77.184.1 to 38.77.185.25438.77.185.255510
22238.77.186.0/2338.77.186.1 to 38.77.187.25438.77.187.255510
22338.77.188.0/2338.77.188.1 to 38.77.189.25438.77.189.255510
22438.77.190.0/2338.77.190.1 to 38.77.191.25438.77.191.255510
22538.77.192.0/2338.77.192.1 to 38.77.193.25438.77.193.255510
22638.77.194.0/2338.77.194.1 to 38.77.195.25438.77.195.255510
22738.77.196.0/2338.77.196.1 to 38.77.197.25438.77.197.255510
22838.77.198.0/2338.77.198.1 to 38.77.199.25438.77.199.255510
22938.77.200.0/2338.77.200.1 to 38.77.201.25438.77.201.255510
23038.77.202.0/2338.77.202.1 to 38.77.203.25438.77.203.255510
23138.77.204.0/2338.77.204.1 to 38.77.205.25438.77.205.255510
23238.77.206.0/2338.77.206.1 to 38.77.207.25438.77.207.255510
23338.77.208.0/2338.77.208.1 to 38.77.209.25438.77.209.255510
23438.77.210.0/2338.77.210.1 to 38.77.211.25438.77.211.255510
23538.77.212.0/2338.77.212.1 to 38.77.213.25438.77.213.255510
23638.77.214.0/2338.77.214.1 to 38.77.215.25438.77.215.255510
23738.77.216.0/2338.77.216.1 to 38.77.217.25438.77.217.255510
23838.77.218.0/2338.77.218.1 to 38.77.219.25438.77.219.255510
23938.77.220.0/2338.77.220.1 to 38.77.221.25438.77.221.255510
24038.77.222.0/2338.77.222.1 to 38.77.223.25438.77.223.255510
24138.77.224.0/2338.77.224.1 to 38.77.225.25438.77.225.255510
24238.77.226.0/2338.77.226.1 to 38.77.227.25438.77.227.255510
24338.77.228.0/2338.77.228.1 to 38.77.229.25438.77.229.255510
24438.77.230.0/2338.77.230.1 to 38.77.231.25438.77.231.255510
24538.77.232.0/2338.77.232.1 to 38.77.233.25438.77.233.255510
24638.77.234.0/2338.77.234.1 to 38.77.235.25438.77.235.255510
24738.77.236.0/2338.77.236.1 to 38.77.237.25438.77.237.255510
24838.77.238.0/2338.77.238.1 to 38.77.239.25438.77.239.255510
24938.77.240.0/2338.77.240.1 to 38.77.241.25438.77.241.255510
25038.77.242.0/2338.77.242.1 to 38.77.243.25438.77.243.255510
25138.77.244.0/2338.77.244.1 to 38.77.245.25438.77.245.255510
25238.77.246.0/2338.77.246.1 to 38.77.247.25438.77.247.255510
25338.77.248.0/2338.77.248.1 to 38.77.249.25438.77.249.255510
25438.77.250.0/2338.77.250.1 to 38.77.251.25438.77.251.255510
25538.77.252.0/2338.77.252.1 to 38.77.253.25438.77.253.255510
25638.77.254.0/2338.77.254.1 to 38.77.255.25438.77.255.255510

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