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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.

Network90.167.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
90.167.0.0
Broadcast address
90.167.255.255
First usable
90.167.0.1
Last usable
90.167.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 5AA70000 · Integer 1520893952 to 1520959487
Reverse DNS zone
167.90.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011010.10100111..00000000.0000000090.167.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01011010.10100111..00000000.0000000090.167.0.0
Broadcast01011010.10100111..11111111.1111111190.167.255.255
Split into smaller subnets/24

90.167.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
190.167.0.0/2490.167.0.1 to 90.167.0.25490.167.0.255254
290.167.1.0/2490.167.1.1 to 90.167.1.25490.167.1.255254
390.167.2.0/2490.167.2.1 to 90.167.2.25490.167.2.255254
490.167.3.0/2490.167.3.1 to 90.167.3.25490.167.3.255254
590.167.4.0/2490.167.4.1 to 90.167.4.25490.167.4.255254
690.167.5.0/2490.167.5.1 to 90.167.5.25490.167.5.255254
790.167.6.0/2490.167.6.1 to 90.167.6.25490.167.6.255254
890.167.7.0/2490.167.7.1 to 90.167.7.25490.167.7.255254
990.167.8.0/2490.167.8.1 to 90.167.8.25490.167.8.255254
1090.167.9.0/2490.167.9.1 to 90.167.9.25490.167.9.255254
1190.167.10.0/2490.167.10.1 to 90.167.10.25490.167.10.255254
1290.167.11.0/2490.167.11.1 to 90.167.11.25490.167.11.255254
1390.167.12.0/2490.167.12.1 to 90.167.12.25490.167.12.255254
1490.167.13.0/2490.167.13.1 to 90.167.13.25490.167.13.255254
1590.167.14.0/2490.167.14.1 to 90.167.14.25490.167.14.255254
1690.167.15.0/2490.167.15.1 to 90.167.15.25490.167.15.255254
1790.167.16.0/2490.167.16.1 to 90.167.16.25490.167.16.255254
1890.167.17.0/2490.167.17.1 to 90.167.17.25490.167.17.255254
1990.167.18.0/2490.167.18.1 to 90.167.18.25490.167.18.255254
2090.167.19.0/2490.167.19.1 to 90.167.19.25490.167.19.255254
2190.167.20.0/2490.167.20.1 to 90.167.20.25490.167.20.255254
2290.167.21.0/2490.167.21.1 to 90.167.21.25490.167.21.255254
2390.167.22.0/2490.167.22.1 to 90.167.22.25490.167.22.255254
2490.167.23.0/2490.167.23.1 to 90.167.23.25490.167.23.255254
2590.167.24.0/2490.167.24.1 to 90.167.24.25490.167.24.255254
2690.167.25.0/2490.167.25.1 to 90.167.25.25490.167.25.255254
2790.167.26.0/2490.167.26.1 to 90.167.26.25490.167.26.255254
2890.167.27.0/2490.167.27.1 to 90.167.27.25490.167.27.255254
2990.167.28.0/2490.167.28.1 to 90.167.28.25490.167.28.255254
3090.167.29.0/2490.167.29.1 to 90.167.29.25490.167.29.255254
3190.167.30.0/2490.167.30.1 to 90.167.30.25490.167.30.255254
3290.167.31.0/2490.167.31.1 to 90.167.31.25490.167.31.255254
3390.167.32.0/2490.167.32.1 to 90.167.32.25490.167.32.255254
3490.167.33.0/2490.167.33.1 to 90.167.33.25490.167.33.255254
3590.167.34.0/2490.167.34.1 to 90.167.34.25490.167.34.255254
3690.167.35.0/2490.167.35.1 to 90.167.35.25490.167.35.255254
3790.167.36.0/2490.167.36.1 to 90.167.36.25490.167.36.255254
3890.167.37.0/2490.167.37.1 to 90.167.37.25490.167.37.255254
3990.167.38.0/2490.167.38.1 to 90.167.38.25490.167.38.255254
4090.167.39.0/2490.167.39.1 to 90.167.39.25490.167.39.255254
4190.167.40.0/2490.167.40.1 to 90.167.40.25490.167.40.255254
4290.167.41.0/2490.167.41.1 to 90.167.41.25490.167.41.255254
4390.167.42.0/2490.167.42.1 to 90.167.42.25490.167.42.255254
4490.167.43.0/2490.167.43.1 to 90.167.43.25490.167.43.255254
4590.167.44.0/2490.167.44.1 to 90.167.44.25490.167.44.255254
4690.167.45.0/2490.167.45.1 to 90.167.45.25490.167.45.255254
4790.167.46.0/2490.167.46.1 to 90.167.46.25490.167.46.255254
4890.167.47.0/2490.167.47.1 to 90.167.47.25490.167.47.255254
4990.167.48.0/2490.167.48.1 to 90.167.48.25490.167.48.255254
5090.167.49.0/2490.167.49.1 to 90.167.49.25490.167.49.255254
5190.167.50.0/2490.167.50.1 to 90.167.50.25490.167.50.255254
5290.167.51.0/2490.167.51.1 to 90.167.51.25490.167.51.255254
5390.167.52.0/2490.167.52.1 to 90.167.52.25490.167.52.255254
5490.167.53.0/2490.167.53.1 to 90.167.53.25490.167.53.255254
5590.167.54.0/2490.167.54.1 to 90.167.54.25490.167.54.255254
5690.167.55.0/2490.167.55.1 to 90.167.55.25490.167.55.255254
5790.167.56.0/2490.167.56.1 to 90.167.56.25490.167.56.255254
5890.167.57.0/2490.167.57.1 to 90.167.57.25490.167.57.255254
5990.167.58.0/2490.167.58.1 to 90.167.58.25490.167.58.255254
6090.167.59.0/2490.167.59.1 to 90.167.59.25490.167.59.255254
6190.167.60.0/2490.167.60.1 to 90.167.60.25490.167.60.255254
6290.167.61.0/2490.167.61.1 to 90.167.61.25490.167.61.255254
6390.167.62.0/2490.167.62.1 to 90.167.62.25490.167.62.255254
6490.167.63.0/2490.167.63.1 to 90.167.63.25490.167.63.255254
6590.167.64.0/2490.167.64.1 to 90.167.64.25490.167.64.255254
6690.167.65.0/2490.167.65.1 to 90.167.65.25490.167.65.255254
6790.167.66.0/2490.167.66.1 to 90.167.66.25490.167.66.255254
6890.167.67.0/2490.167.67.1 to 90.167.67.25490.167.67.255254
6990.167.68.0/2490.167.68.1 to 90.167.68.25490.167.68.255254
7090.167.69.0/2490.167.69.1 to 90.167.69.25490.167.69.255254
7190.167.70.0/2490.167.70.1 to 90.167.70.25490.167.70.255254
7290.167.71.0/2490.167.71.1 to 90.167.71.25490.167.71.255254
7390.167.72.0/2490.167.72.1 to 90.167.72.25490.167.72.255254
7490.167.73.0/2490.167.73.1 to 90.167.73.25490.167.73.255254
7590.167.74.0/2490.167.74.1 to 90.167.74.25490.167.74.255254
7690.167.75.0/2490.167.75.1 to 90.167.75.25490.167.75.255254
7790.167.76.0/2490.167.76.1 to 90.167.76.25490.167.76.255254
7890.167.77.0/2490.167.77.1 to 90.167.77.25490.167.77.255254
7990.167.78.0/2490.167.78.1 to 90.167.78.25490.167.78.255254
8090.167.79.0/2490.167.79.1 to 90.167.79.25490.167.79.255254
8190.167.80.0/2490.167.80.1 to 90.167.80.25490.167.80.255254
8290.167.81.0/2490.167.81.1 to 90.167.81.25490.167.81.255254
8390.167.82.0/2490.167.82.1 to 90.167.82.25490.167.82.255254
8490.167.83.0/2490.167.83.1 to 90.167.83.25490.167.83.255254
8590.167.84.0/2490.167.84.1 to 90.167.84.25490.167.84.255254
8690.167.85.0/2490.167.85.1 to 90.167.85.25490.167.85.255254
8790.167.86.0/2490.167.86.1 to 90.167.86.25490.167.86.255254
8890.167.87.0/2490.167.87.1 to 90.167.87.25490.167.87.255254
8990.167.88.0/2490.167.88.1 to 90.167.88.25490.167.88.255254
9090.167.89.0/2490.167.89.1 to 90.167.89.25490.167.89.255254
9190.167.90.0/2490.167.90.1 to 90.167.90.25490.167.90.255254
9290.167.91.0/2490.167.91.1 to 90.167.91.25490.167.91.255254
9390.167.92.0/2490.167.92.1 to 90.167.92.25490.167.92.255254
9490.167.93.0/2490.167.93.1 to 90.167.93.25490.167.93.255254
9590.167.94.0/2490.167.94.1 to 90.167.94.25490.167.94.255254
9690.167.95.0/2490.167.95.1 to 90.167.95.25490.167.95.255254
9790.167.96.0/2490.167.96.1 to 90.167.96.25490.167.96.255254
9890.167.97.0/2490.167.97.1 to 90.167.97.25490.167.97.255254
9990.167.98.0/2490.167.98.1 to 90.167.98.25490.167.98.255254
10090.167.99.0/2490.167.99.1 to 90.167.99.25490.167.99.255254
10190.167.100.0/2490.167.100.1 to 90.167.100.25490.167.100.255254
10290.167.101.0/2490.167.101.1 to 90.167.101.25490.167.101.255254
10390.167.102.0/2490.167.102.1 to 90.167.102.25490.167.102.255254
10490.167.103.0/2490.167.103.1 to 90.167.103.25490.167.103.255254
10590.167.104.0/2490.167.104.1 to 90.167.104.25490.167.104.255254
10690.167.105.0/2490.167.105.1 to 90.167.105.25490.167.105.255254
10790.167.106.0/2490.167.106.1 to 90.167.106.25490.167.106.255254
10890.167.107.0/2490.167.107.1 to 90.167.107.25490.167.107.255254
10990.167.108.0/2490.167.108.1 to 90.167.108.25490.167.108.255254
11090.167.109.0/2490.167.109.1 to 90.167.109.25490.167.109.255254
11190.167.110.0/2490.167.110.1 to 90.167.110.25490.167.110.255254
11290.167.111.0/2490.167.111.1 to 90.167.111.25490.167.111.255254
11390.167.112.0/2490.167.112.1 to 90.167.112.25490.167.112.255254
11490.167.113.0/2490.167.113.1 to 90.167.113.25490.167.113.255254
11590.167.114.0/2490.167.114.1 to 90.167.114.25490.167.114.255254
11690.167.115.0/2490.167.115.1 to 90.167.115.25490.167.115.255254
11790.167.116.0/2490.167.116.1 to 90.167.116.25490.167.116.255254
11890.167.117.0/2490.167.117.1 to 90.167.117.25490.167.117.255254
11990.167.118.0/2490.167.118.1 to 90.167.118.25490.167.118.255254
12090.167.119.0/2490.167.119.1 to 90.167.119.25490.167.119.255254
12190.167.120.0/2490.167.120.1 to 90.167.120.25490.167.120.255254
12290.167.121.0/2490.167.121.1 to 90.167.121.25490.167.121.255254
12390.167.122.0/2490.167.122.1 to 90.167.122.25490.167.122.255254
12490.167.123.0/2490.167.123.1 to 90.167.123.25490.167.123.255254
12590.167.124.0/2490.167.124.1 to 90.167.124.25490.167.124.255254
12690.167.125.0/2490.167.125.1 to 90.167.125.25490.167.125.255254
12790.167.126.0/2490.167.126.1 to 90.167.126.25490.167.126.255254
12890.167.127.0/2490.167.127.1 to 90.167.127.25490.167.127.255254
12990.167.128.0/2490.167.128.1 to 90.167.128.25490.167.128.255254
13090.167.129.0/2490.167.129.1 to 90.167.129.25490.167.129.255254
13190.167.130.0/2490.167.130.1 to 90.167.130.25490.167.130.255254
13290.167.131.0/2490.167.131.1 to 90.167.131.25490.167.131.255254
13390.167.132.0/2490.167.132.1 to 90.167.132.25490.167.132.255254
13490.167.133.0/2490.167.133.1 to 90.167.133.25490.167.133.255254
13590.167.134.0/2490.167.134.1 to 90.167.134.25490.167.134.255254
13690.167.135.0/2490.167.135.1 to 90.167.135.25490.167.135.255254
13790.167.136.0/2490.167.136.1 to 90.167.136.25490.167.136.255254
13890.167.137.0/2490.167.137.1 to 90.167.137.25490.167.137.255254
13990.167.138.0/2490.167.138.1 to 90.167.138.25490.167.138.255254
14090.167.139.0/2490.167.139.1 to 90.167.139.25490.167.139.255254
14190.167.140.0/2490.167.140.1 to 90.167.140.25490.167.140.255254
14290.167.141.0/2490.167.141.1 to 90.167.141.25490.167.141.255254
14390.167.142.0/2490.167.142.1 to 90.167.142.25490.167.142.255254
14490.167.143.0/2490.167.143.1 to 90.167.143.25490.167.143.255254
14590.167.144.0/2490.167.144.1 to 90.167.144.25490.167.144.255254
14690.167.145.0/2490.167.145.1 to 90.167.145.25490.167.145.255254
14790.167.146.0/2490.167.146.1 to 90.167.146.25490.167.146.255254
14890.167.147.0/2490.167.147.1 to 90.167.147.25490.167.147.255254
14990.167.148.0/2490.167.148.1 to 90.167.148.25490.167.148.255254
15090.167.149.0/2490.167.149.1 to 90.167.149.25490.167.149.255254
15190.167.150.0/2490.167.150.1 to 90.167.150.25490.167.150.255254
15290.167.151.0/2490.167.151.1 to 90.167.151.25490.167.151.255254
15390.167.152.0/2490.167.152.1 to 90.167.152.25490.167.152.255254
15490.167.153.0/2490.167.153.1 to 90.167.153.25490.167.153.255254
15590.167.154.0/2490.167.154.1 to 90.167.154.25490.167.154.255254
15690.167.155.0/2490.167.155.1 to 90.167.155.25490.167.155.255254
15790.167.156.0/2490.167.156.1 to 90.167.156.25490.167.156.255254
15890.167.157.0/2490.167.157.1 to 90.167.157.25490.167.157.255254
15990.167.158.0/2490.167.158.1 to 90.167.158.25490.167.158.255254
16090.167.159.0/2490.167.159.1 to 90.167.159.25490.167.159.255254
16190.167.160.0/2490.167.160.1 to 90.167.160.25490.167.160.255254
16290.167.161.0/2490.167.161.1 to 90.167.161.25490.167.161.255254
16390.167.162.0/2490.167.162.1 to 90.167.162.25490.167.162.255254
16490.167.163.0/2490.167.163.1 to 90.167.163.25490.167.163.255254
16590.167.164.0/2490.167.164.1 to 90.167.164.25490.167.164.255254
16690.167.165.0/2490.167.165.1 to 90.167.165.25490.167.165.255254
16790.167.166.0/2490.167.166.1 to 90.167.166.25490.167.166.255254
16890.167.167.0/2490.167.167.1 to 90.167.167.25490.167.167.255254
16990.167.168.0/2490.167.168.1 to 90.167.168.25490.167.168.255254
17090.167.169.0/2490.167.169.1 to 90.167.169.25490.167.169.255254
17190.167.170.0/2490.167.170.1 to 90.167.170.25490.167.170.255254
17290.167.171.0/2490.167.171.1 to 90.167.171.25490.167.171.255254
17390.167.172.0/2490.167.172.1 to 90.167.172.25490.167.172.255254
17490.167.173.0/2490.167.173.1 to 90.167.173.25490.167.173.255254
17590.167.174.0/2490.167.174.1 to 90.167.174.25490.167.174.255254
17690.167.175.0/2490.167.175.1 to 90.167.175.25490.167.175.255254
17790.167.176.0/2490.167.176.1 to 90.167.176.25490.167.176.255254
17890.167.177.0/2490.167.177.1 to 90.167.177.25490.167.177.255254
17990.167.178.0/2490.167.178.1 to 90.167.178.25490.167.178.255254
18090.167.179.0/2490.167.179.1 to 90.167.179.25490.167.179.255254
18190.167.180.0/2490.167.180.1 to 90.167.180.25490.167.180.255254
18290.167.181.0/2490.167.181.1 to 90.167.181.25490.167.181.255254
18390.167.182.0/2490.167.182.1 to 90.167.182.25490.167.182.255254
18490.167.183.0/2490.167.183.1 to 90.167.183.25490.167.183.255254
18590.167.184.0/2490.167.184.1 to 90.167.184.25490.167.184.255254
18690.167.185.0/2490.167.185.1 to 90.167.185.25490.167.185.255254
18790.167.186.0/2490.167.186.1 to 90.167.186.25490.167.186.255254
18890.167.187.0/2490.167.187.1 to 90.167.187.25490.167.187.255254
18990.167.188.0/2490.167.188.1 to 90.167.188.25490.167.188.255254
19090.167.189.0/2490.167.189.1 to 90.167.189.25490.167.189.255254
19190.167.190.0/2490.167.190.1 to 90.167.190.25490.167.190.255254
19290.167.191.0/2490.167.191.1 to 90.167.191.25490.167.191.255254
19390.167.192.0/2490.167.192.1 to 90.167.192.25490.167.192.255254
19490.167.193.0/2490.167.193.1 to 90.167.193.25490.167.193.255254
19590.167.194.0/2490.167.194.1 to 90.167.194.25490.167.194.255254
19690.167.195.0/2490.167.195.1 to 90.167.195.25490.167.195.255254
19790.167.196.0/2490.167.196.1 to 90.167.196.25490.167.196.255254
19890.167.197.0/2490.167.197.1 to 90.167.197.25490.167.197.255254
19990.167.198.0/2490.167.198.1 to 90.167.198.25490.167.198.255254
20090.167.199.0/2490.167.199.1 to 90.167.199.25490.167.199.255254
20190.167.200.0/2490.167.200.1 to 90.167.200.25490.167.200.255254
20290.167.201.0/2490.167.201.1 to 90.167.201.25490.167.201.255254
20390.167.202.0/2490.167.202.1 to 90.167.202.25490.167.202.255254
20490.167.203.0/2490.167.203.1 to 90.167.203.25490.167.203.255254
20590.167.204.0/2490.167.204.1 to 90.167.204.25490.167.204.255254
20690.167.205.0/2490.167.205.1 to 90.167.205.25490.167.205.255254
20790.167.206.0/2490.167.206.1 to 90.167.206.25490.167.206.255254
20890.167.207.0/2490.167.207.1 to 90.167.207.25490.167.207.255254
20990.167.208.0/2490.167.208.1 to 90.167.208.25490.167.208.255254
21090.167.209.0/2490.167.209.1 to 90.167.209.25490.167.209.255254
21190.167.210.0/2490.167.210.1 to 90.167.210.25490.167.210.255254
21290.167.211.0/2490.167.211.1 to 90.167.211.25490.167.211.255254
21390.167.212.0/2490.167.212.1 to 90.167.212.25490.167.212.255254
21490.167.213.0/2490.167.213.1 to 90.167.213.25490.167.213.255254
21590.167.214.0/2490.167.214.1 to 90.167.214.25490.167.214.255254
21690.167.215.0/2490.167.215.1 to 90.167.215.25490.167.215.255254
21790.167.216.0/2490.167.216.1 to 90.167.216.25490.167.216.255254
21890.167.217.0/2490.167.217.1 to 90.167.217.25490.167.217.255254
21990.167.218.0/2490.167.218.1 to 90.167.218.25490.167.218.255254
22090.167.219.0/2490.167.219.1 to 90.167.219.25490.167.219.255254
22190.167.220.0/2490.167.220.1 to 90.167.220.25490.167.220.255254
22290.167.221.0/2490.167.221.1 to 90.167.221.25490.167.221.255254
22390.167.222.0/2490.167.222.1 to 90.167.222.25490.167.222.255254
22490.167.223.0/2490.167.223.1 to 90.167.223.25490.167.223.255254
22590.167.224.0/2490.167.224.1 to 90.167.224.25490.167.224.255254
22690.167.225.0/2490.167.225.1 to 90.167.225.25490.167.225.255254
22790.167.226.0/2490.167.226.1 to 90.167.226.25490.167.226.255254
22890.167.227.0/2490.167.227.1 to 90.167.227.25490.167.227.255254
22990.167.228.0/2490.167.228.1 to 90.167.228.25490.167.228.255254
23090.167.229.0/2490.167.229.1 to 90.167.229.25490.167.229.255254
23190.167.230.0/2490.167.230.1 to 90.167.230.25490.167.230.255254
23290.167.231.0/2490.167.231.1 to 90.167.231.25490.167.231.255254
23390.167.232.0/2490.167.232.1 to 90.167.232.25490.167.232.255254
23490.167.233.0/2490.167.233.1 to 90.167.233.25490.167.233.255254
23590.167.234.0/2490.167.234.1 to 90.167.234.25490.167.234.255254
23690.167.235.0/2490.167.235.1 to 90.167.235.25490.167.235.255254
23790.167.236.0/2490.167.236.1 to 90.167.236.25490.167.236.255254
23890.167.237.0/2490.167.237.1 to 90.167.237.25490.167.237.255254
23990.167.238.0/2490.167.238.1 to 90.167.238.25490.167.238.255254
24090.167.239.0/2490.167.239.1 to 90.167.239.25490.167.239.255254
24190.167.240.0/2490.167.240.1 to 90.167.240.25490.167.240.255254
24290.167.241.0/2490.167.241.1 to 90.167.241.25490.167.241.255254
24390.167.242.0/2490.167.242.1 to 90.167.242.25490.167.242.255254
24490.167.243.0/2490.167.243.1 to 90.167.243.25490.167.243.255254
24590.167.244.0/2490.167.244.1 to 90.167.244.25490.167.244.255254
24690.167.245.0/2490.167.245.1 to 90.167.245.25490.167.245.255254
24790.167.246.0/2490.167.246.1 to 90.167.246.25490.167.246.255254
24890.167.247.0/2490.167.247.1 to 90.167.247.25490.167.247.255254
24990.167.248.0/2490.167.248.1 to 90.167.248.25490.167.248.255254
25090.167.249.0/2490.167.249.1 to 90.167.249.25490.167.249.255254
25190.167.250.0/2490.167.250.1 to 90.167.250.25490.167.250.255254
25290.167.251.0/2490.167.251.1 to 90.167.251.25490.167.251.255254
25390.167.252.0/2490.167.252.1 to 90.167.252.25490.167.252.255254
25490.167.253.0/2490.167.253.1 to 90.167.253.25490.167.253.255254
25590.167.254.0/2490.167.254.1 to 90.167.254.25490.167.254.255254
25690.167.255.0/2490.167.255.1 to 90.167.255.25490.167.255.255254

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