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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.

Network67.153.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
67.153.0.0
Broadcast address
67.153.255.255
First usable
67.153.0.1
Last usable
67.153.255.254
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 43990000 · Integer 1134100480 to 1134166015
Reverse DNS zone
153.67.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01000011.10011001..00000000.0000000067.153.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01000011.10011001..00000000.0000000067.153.0.0
Broadcast01000011.10011001..11111111.1111111167.153.255.255
Split into smaller subnets/24

67.153.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
167.153.0.0/2467.153.0.1 to 67.153.0.25467.153.0.255254
267.153.1.0/2467.153.1.1 to 67.153.1.25467.153.1.255254
367.153.2.0/2467.153.2.1 to 67.153.2.25467.153.2.255254
467.153.3.0/2467.153.3.1 to 67.153.3.25467.153.3.255254
567.153.4.0/2467.153.4.1 to 67.153.4.25467.153.4.255254
667.153.5.0/2467.153.5.1 to 67.153.5.25467.153.5.255254
767.153.6.0/2467.153.6.1 to 67.153.6.25467.153.6.255254
867.153.7.0/2467.153.7.1 to 67.153.7.25467.153.7.255254
967.153.8.0/2467.153.8.1 to 67.153.8.25467.153.8.255254
1067.153.9.0/2467.153.9.1 to 67.153.9.25467.153.9.255254
1167.153.10.0/2467.153.10.1 to 67.153.10.25467.153.10.255254
1267.153.11.0/2467.153.11.1 to 67.153.11.25467.153.11.255254
1367.153.12.0/2467.153.12.1 to 67.153.12.25467.153.12.255254
1467.153.13.0/2467.153.13.1 to 67.153.13.25467.153.13.255254
1567.153.14.0/2467.153.14.1 to 67.153.14.25467.153.14.255254
1667.153.15.0/2467.153.15.1 to 67.153.15.25467.153.15.255254
1767.153.16.0/2467.153.16.1 to 67.153.16.25467.153.16.255254
1867.153.17.0/2467.153.17.1 to 67.153.17.25467.153.17.255254
1967.153.18.0/2467.153.18.1 to 67.153.18.25467.153.18.255254
2067.153.19.0/2467.153.19.1 to 67.153.19.25467.153.19.255254
2167.153.20.0/2467.153.20.1 to 67.153.20.25467.153.20.255254
2267.153.21.0/2467.153.21.1 to 67.153.21.25467.153.21.255254
2367.153.22.0/2467.153.22.1 to 67.153.22.25467.153.22.255254
2467.153.23.0/2467.153.23.1 to 67.153.23.25467.153.23.255254
2567.153.24.0/2467.153.24.1 to 67.153.24.25467.153.24.255254
2667.153.25.0/2467.153.25.1 to 67.153.25.25467.153.25.255254
2767.153.26.0/2467.153.26.1 to 67.153.26.25467.153.26.255254
2867.153.27.0/2467.153.27.1 to 67.153.27.25467.153.27.255254
2967.153.28.0/2467.153.28.1 to 67.153.28.25467.153.28.255254
3067.153.29.0/2467.153.29.1 to 67.153.29.25467.153.29.255254
3167.153.30.0/2467.153.30.1 to 67.153.30.25467.153.30.255254
3267.153.31.0/2467.153.31.1 to 67.153.31.25467.153.31.255254
3367.153.32.0/2467.153.32.1 to 67.153.32.25467.153.32.255254
3467.153.33.0/2467.153.33.1 to 67.153.33.25467.153.33.255254
3567.153.34.0/2467.153.34.1 to 67.153.34.25467.153.34.255254
3667.153.35.0/2467.153.35.1 to 67.153.35.25467.153.35.255254
3767.153.36.0/2467.153.36.1 to 67.153.36.25467.153.36.255254
3867.153.37.0/2467.153.37.1 to 67.153.37.25467.153.37.255254
3967.153.38.0/2467.153.38.1 to 67.153.38.25467.153.38.255254
4067.153.39.0/2467.153.39.1 to 67.153.39.25467.153.39.255254
4167.153.40.0/2467.153.40.1 to 67.153.40.25467.153.40.255254
4267.153.41.0/2467.153.41.1 to 67.153.41.25467.153.41.255254
4367.153.42.0/2467.153.42.1 to 67.153.42.25467.153.42.255254
4467.153.43.0/2467.153.43.1 to 67.153.43.25467.153.43.255254
4567.153.44.0/2467.153.44.1 to 67.153.44.25467.153.44.255254
4667.153.45.0/2467.153.45.1 to 67.153.45.25467.153.45.255254
4767.153.46.0/2467.153.46.1 to 67.153.46.25467.153.46.255254
4867.153.47.0/2467.153.47.1 to 67.153.47.25467.153.47.255254
4967.153.48.0/2467.153.48.1 to 67.153.48.25467.153.48.255254
5067.153.49.0/2467.153.49.1 to 67.153.49.25467.153.49.255254
5167.153.50.0/2467.153.50.1 to 67.153.50.25467.153.50.255254
5267.153.51.0/2467.153.51.1 to 67.153.51.25467.153.51.255254
5367.153.52.0/2467.153.52.1 to 67.153.52.25467.153.52.255254
5467.153.53.0/2467.153.53.1 to 67.153.53.25467.153.53.255254
5567.153.54.0/2467.153.54.1 to 67.153.54.25467.153.54.255254
5667.153.55.0/2467.153.55.1 to 67.153.55.25467.153.55.255254
5767.153.56.0/2467.153.56.1 to 67.153.56.25467.153.56.255254
5867.153.57.0/2467.153.57.1 to 67.153.57.25467.153.57.255254
5967.153.58.0/2467.153.58.1 to 67.153.58.25467.153.58.255254
6067.153.59.0/2467.153.59.1 to 67.153.59.25467.153.59.255254
6167.153.60.0/2467.153.60.1 to 67.153.60.25467.153.60.255254
6267.153.61.0/2467.153.61.1 to 67.153.61.25467.153.61.255254
6367.153.62.0/2467.153.62.1 to 67.153.62.25467.153.62.255254
6467.153.63.0/2467.153.63.1 to 67.153.63.25467.153.63.255254
6567.153.64.0/2467.153.64.1 to 67.153.64.25467.153.64.255254
6667.153.65.0/2467.153.65.1 to 67.153.65.25467.153.65.255254
6767.153.66.0/2467.153.66.1 to 67.153.66.25467.153.66.255254
6867.153.67.0/2467.153.67.1 to 67.153.67.25467.153.67.255254
6967.153.68.0/2467.153.68.1 to 67.153.68.25467.153.68.255254
7067.153.69.0/2467.153.69.1 to 67.153.69.25467.153.69.255254
7167.153.70.0/2467.153.70.1 to 67.153.70.25467.153.70.255254
7267.153.71.0/2467.153.71.1 to 67.153.71.25467.153.71.255254
7367.153.72.0/2467.153.72.1 to 67.153.72.25467.153.72.255254
7467.153.73.0/2467.153.73.1 to 67.153.73.25467.153.73.255254
7567.153.74.0/2467.153.74.1 to 67.153.74.25467.153.74.255254
7667.153.75.0/2467.153.75.1 to 67.153.75.25467.153.75.255254
7767.153.76.0/2467.153.76.1 to 67.153.76.25467.153.76.255254
7867.153.77.0/2467.153.77.1 to 67.153.77.25467.153.77.255254
7967.153.78.0/2467.153.78.1 to 67.153.78.25467.153.78.255254
8067.153.79.0/2467.153.79.1 to 67.153.79.25467.153.79.255254
8167.153.80.0/2467.153.80.1 to 67.153.80.25467.153.80.255254
8267.153.81.0/2467.153.81.1 to 67.153.81.25467.153.81.255254
8367.153.82.0/2467.153.82.1 to 67.153.82.25467.153.82.255254
8467.153.83.0/2467.153.83.1 to 67.153.83.25467.153.83.255254
8567.153.84.0/2467.153.84.1 to 67.153.84.25467.153.84.255254
8667.153.85.0/2467.153.85.1 to 67.153.85.25467.153.85.255254
8767.153.86.0/2467.153.86.1 to 67.153.86.25467.153.86.255254
8867.153.87.0/2467.153.87.1 to 67.153.87.25467.153.87.255254
8967.153.88.0/2467.153.88.1 to 67.153.88.25467.153.88.255254
9067.153.89.0/2467.153.89.1 to 67.153.89.25467.153.89.255254
9167.153.90.0/2467.153.90.1 to 67.153.90.25467.153.90.255254
9267.153.91.0/2467.153.91.1 to 67.153.91.25467.153.91.255254
9367.153.92.0/2467.153.92.1 to 67.153.92.25467.153.92.255254
9467.153.93.0/2467.153.93.1 to 67.153.93.25467.153.93.255254
9567.153.94.0/2467.153.94.1 to 67.153.94.25467.153.94.255254
9667.153.95.0/2467.153.95.1 to 67.153.95.25467.153.95.255254
9767.153.96.0/2467.153.96.1 to 67.153.96.25467.153.96.255254
9867.153.97.0/2467.153.97.1 to 67.153.97.25467.153.97.255254
9967.153.98.0/2467.153.98.1 to 67.153.98.25467.153.98.255254
10067.153.99.0/2467.153.99.1 to 67.153.99.25467.153.99.255254
10167.153.100.0/2467.153.100.1 to 67.153.100.25467.153.100.255254
10267.153.101.0/2467.153.101.1 to 67.153.101.25467.153.101.255254
10367.153.102.0/2467.153.102.1 to 67.153.102.25467.153.102.255254
10467.153.103.0/2467.153.103.1 to 67.153.103.25467.153.103.255254
10567.153.104.0/2467.153.104.1 to 67.153.104.25467.153.104.255254
10667.153.105.0/2467.153.105.1 to 67.153.105.25467.153.105.255254
10767.153.106.0/2467.153.106.1 to 67.153.106.25467.153.106.255254
10867.153.107.0/2467.153.107.1 to 67.153.107.25467.153.107.255254
10967.153.108.0/2467.153.108.1 to 67.153.108.25467.153.108.255254
11067.153.109.0/2467.153.109.1 to 67.153.109.25467.153.109.255254
11167.153.110.0/2467.153.110.1 to 67.153.110.25467.153.110.255254
11267.153.111.0/2467.153.111.1 to 67.153.111.25467.153.111.255254
11367.153.112.0/2467.153.112.1 to 67.153.112.25467.153.112.255254
11467.153.113.0/2467.153.113.1 to 67.153.113.25467.153.113.255254
11567.153.114.0/2467.153.114.1 to 67.153.114.25467.153.114.255254
11667.153.115.0/2467.153.115.1 to 67.153.115.25467.153.115.255254
11767.153.116.0/2467.153.116.1 to 67.153.116.25467.153.116.255254
11867.153.117.0/2467.153.117.1 to 67.153.117.25467.153.117.255254
11967.153.118.0/2467.153.118.1 to 67.153.118.25467.153.118.255254
12067.153.119.0/2467.153.119.1 to 67.153.119.25467.153.119.255254
12167.153.120.0/2467.153.120.1 to 67.153.120.25467.153.120.255254
12267.153.121.0/2467.153.121.1 to 67.153.121.25467.153.121.255254
12367.153.122.0/2467.153.122.1 to 67.153.122.25467.153.122.255254
12467.153.123.0/2467.153.123.1 to 67.153.123.25467.153.123.255254
12567.153.124.0/2467.153.124.1 to 67.153.124.25467.153.124.255254
12667.153.125.0/2467.153.125.1 to 67.153.125.25467.153.125.255254
12767.153.126.0/2467.153.126.1 to 67.153.126.25467.153.126.255254
12867.153.127.0/2467.153.127.1 to 67.153.127.25467.153.127.255254
12967.153.128.0/2467.153.128.1 to 67.153.128.25467.153.128.255254
13067.153.129.0/2467.153.129.1 to 67.153.129.25467.153.129.255254
13167.153.130.0/2467.153.130.1 to 67.153.130.25467.153.130.255254
13267.153.131.0/2467.153.131.1 to 67.153.131.25467.153.131.255254
13367.153.132.0/2467.153.132.1 to 67.153.132.25467.153.132.255254
13467.153.133.0/2467.153.133.1 to 67.153.133.25467.153.133.255254
13567.153.134.0/2467.153.134.1 to 67.153.134.25467.153.134.255254
13667.153.135.0/2467.153.135.1 to 67.153.135.25467.153.135.255254
13767.153.136.0/2467.153.136.1 to 67.153.136.25467.153.136.255254
13867.153.137.0/2467.153.137.1 to 67.153.137.25467.153.137.255254
13967.153.138.0/2467.153.138.1 to 67.153.138.25467.153.138.255254
14067.153.139.0/2467.153.139.1 to 67.153.139.25467.153.139.255254
14167.153.140.0/2467.153.140.1 to 67.153.140.25467.153.140.255254
14267.153.141.0/2467.153.141.1 to 67.153.141.25467.153.141.255254
14367.153.142.0/2467.153.142.1 to 67.153.142.25467.153.142.255254
14467.153.143.0/2467.153.143.1 to 67.153.143.25467.153.143.255254
14567.153.144.0/2467.153.144.1 to 67.153.144.25467.153.144.255254
14667.153.145.0/2467.153.145.1 to 67.153.145.25467.153.145.255254
14767.153.146.0/2467.153.146.1 to 67.153.146.25467.153.146.255254
14867.153.147.0/2467.153.147.1 to 67.153.147.25467.153.147.255254
14967.153.148.0/2467.153.148.1 to 67.153.148.25467.153.148.255254
15067.153.149.0/2467.153.149.1 to 67.153.149.25467.153.149.255254
15167.153.150.0/2467.153.150.1 to 67.153.150.25467.153.150.255254
15267.153.151.0/2467.153.151.1 to 67.153.151.25467.153.151.255254
15367.153.152.0/2467.153.152.1 to 67.153.152.25467.153.152.255254
15467.153.153.0/2467.153.153.1 to 67.153.153.25467.153.153.255254
15567.153.154.0/2467.153.154.1 to 67.153.154.25467.153.154.255254
15667.153.155.0/2467.153.155.1 to 67.153.155.25467.153.155.255254
15767.153.156.0/2467.153.156.1 to 67.153.156.25467.153.156.255254
15867.153.157.0/2467.153.157.1 to 67.153.157.25467.153.157.255254
15967.153.158.0/2467.153.158.1 to 67.153.158.25467.153.158.255254
16067.153.159.0/2467.153.159.1 to 67.153.159.25467.153.159.255254
16167.153.160.0/2467.153.160.1 to 67.153.160.25467.153.160.255254
16267.153.161.0/2467.153.161.1 to 67.153.161.25467.153.161.255254
16367.153.162.0/2467.153.162.1 to 67.153.162.25467.153.162.255254
16467.153.163.0/2467.153.163.1 to 67.153.163.25467.153.163.255254
16567.153.164.0/2467.153.164.1 to 67.153.164.25467.153.164.255254
16667.153.165.0/2467.153.165.1 to 67.153.165.25467.153.165.255254
16767.153.166.0/2467.153.166.1 to 67.153.166.25467.153.166.255254
16867.153.167.0/2467.153.167.1 to 67.153.167.25467.153.167.255254
16967.153.168.0/2467.153.168.1 to 67.153.168.25467.153.168.255254
17067.153.169.0/2467.153.169.1 to 67.153.169.25467.153.169.255254
17167.153.170.0/2467.153.170.1 to 67.153.170.25467.153.170.255254
17267.153.171.0/2467.153.171.1 to 67.153.171.25467.153.171.255254
17367.153.172.0/2467.153.172.1 to 67.153.172.25467.153.172.255254
17467.153.173.0/2467.153.173.1 to 67.153.173.25467.153.173.255254
17567.153.174.0/2467.153.174.1 to 67.153.174.25467.153.174.255254
17667.153.175.0/2467.153.175.1 to 67.153.175.25467.153.175.255254
17767.153.176.0/2467.153.176.1 to 67.153.176.25467.153.176.255254
17867.153.177.0/2467.153.177.1 to 67.153.177.25467.153.177.255254
17967.153.178.0/2467.153.178.1 to 67.153.178.25467.153.178.255254
18067.153.179.0/2467.153.179.1 to 67.153.179.25467.153.179.255254
18167.153.180.0/2467.153.180.1 to 67.153.180.25467.153.180.255254
18267.153.181.0/2467.153.181.1 to 67.153.181.25467.153.181.255254
18367.153.182.0/2467.153.182.1 to 67.153.182.25467.153.182.255254
18467.153.183.0/2467.153.183.1 to 67.153.183.25467.153.183.255254
18567.153.184.0/2467.153.184.1 to 67.153.184.25467.153.184.255254
18667.153.185.0/2467.153.185.1 to 67.153.185.25467.153.185.255254
18767.153.186.0/2467.153.186.1 to 67.153.186.25467.153.186.255254
18867.153.187.0/2467.153.187.1 to 67.153.187.25467.153.187.255254
18967.153.188.0/2467.153.188.1 to 67.153.188.25467.153.188.255254
19067.153.189.0/2467.153.189.1 to 67.153.189.25467.153.189.255254
19167.153.190.0/2467.153.190.1 to 67.153.190.25467.153.190.255254
19267.153.191.0/2467.153.191.1 to 67.153.191.25467.153.191.255254
19367.153.192.0/2467.153.192.1 to 67.153.192.25467.153.192.255254
19467.153.193.0/2467.153.193.1 to 67.153.193.25467.153.193.255254
19567.153.194.0/2467.153.194.1 to 67.153.194.25467.153.194.255254
19667.153.195.0/2467.153.195.1 to 67.153.195.25467.153.195.255254
19767.153.196.0/2467.153.196.1 to 67.153.196.25467.153.196.255254
19867.153.197.0/2467.153.197.1 to 67.153.197.25467.153.197.255254
19967.153.198.0/2467.153.198.1 to 67.153.198.25467.153.198.255254
20067.153.199.0/2467.153.199.1 to 67.153.199.25467.153.199.255254
20167.153.200.0/2467.153.200.1 to 67.153.200.25467.153.200.255254
20267.153.201.0/2467.153.201.1 to 67.153.201.25467.153.201.255254
20367.153.202.0/2467.153.202.1 to 67.153.202.25467.153.202.255254
20467.153.203.0/2467.153.203.1 to 67.153.203.25467.153.203.255254
20567.153.204.0/2467.153.204.1 to 67.153.204.25467.153.204.255254
20667.153.205.0/2467.153.205.1 to 67.153.205.25467.153.205.255254
20767.153.206.0/2467.153.206.1 to 67.153.206.25467.153.206.255254
20867.153.207.0/2467.153.207.1 to 67.153.207.25467.153.207.255254
20967.153.208.0/2467.153.208.1 to 67.153.208.25467.153.208.255254
21067.153.209.0/2467.153.209.1 to 67.153.209.25467.153.209.255254
21167.153.210.0/2467.153.210.1 to 67.153.210.25467.153.210.255254
21267.153.211.0/2467.153.211.1 to 67.153.211.25467.153.211.255254
21367.153.212.0/2467.153.212.1 to 67.153.212.25467.153.212.255254
21467.153.213.0/2467.153.213.1 to 67.153.213.25467.153.213.255254
21567.153.214.0/2467.153.214.1 to 67.153.214.25467.153.214.255254
21667.153.215.0/2467.153.215.1 to 67.153.215.25467.153.215.255254
21767.153.216.0/2467.153.216.1 to 67.153.216.25467.153.216.255254
21867.153.217.0/2467.153.217.1 to 67.153.217.25467.153.217.255254
21967.153.218.0/2467.153.218.1 to 67.153.218.25467.153.218.255254
22067.153.219.0/2467.153.219.1 to 67.153.219.25467.153.219.255254
22167.153.220.0/2467.153.220.1 to 67.153.220.25467.153.220.255254
22267.153.221.0/2467.153.221.1 to 67.153.221.25467.153.221.255254
22367.153.222.0/2467.153.222.1 to 67.153.222.25467.153.222.255254
22467.153.223.0/2467.153.223.1 to 67.153.223.25467.153.223.255254
22567.153.224.0/2467.153.224.1 to 67.153.224.25467.153.224.255254
22667.153.225.0/2467.153.225.1 to 67.153.225.25467.153.225.255254
22767.153.226.0/2467.153.226.1 to 67.153.226.25467.153.226.255254
22867.153.227.0/2467.153.227.1 to 67.153.227.25467.153.227.255254
22967.153.228.0/2467.153.228.1 to 67.153.228.25467.153.228.255254
23067.153.229.0/2467.153.229.1 to 67.153.229.25467.153.229.255254
23167.153.230.0/2467.153.230.1 to 67.153.230.25467.153.230.255254
23267.153.231.0/2467.153.231.1 to 67.153.231.25467.153.231.255254
23367.153.232.0/2467.153.232.1 to 67.153.232.25467.153.232.255254
23467.153.233.0/2467.153.233.1 to 67.153.233.25467.153.233.255254
23567.153.234.0/2467.153.234.1 to 67.153.234.25467.153.234.255254
23667.153.235.0/2467.153.235.1 to 67.153.235.25467.153.235.255254
23767.153.236.0/2467.153.236.1 to 67.153.236.25467.153.236.255254
23867.153.237.0/2467.153.237.1 to 67.153.237.25467.153.237.255254
23967.153.238.0/2467.153.238.1 to 67.153.238.25467.153.238.255254
24067.153.239.0/2467.153.239.1 to 67.153.239.25467.153.239.255254
24167.153.240.0/2467.153.240.1 to 67.153.240.25467.153.240.255254
24267.153.241.0/2467.153.241.1 to 67.153.241.25467.153.241.255254
24367.153.242.0/2467.153.242.1 to 67.153.242.25467.153.242.255254
24467.153.243.0/2467.153.243.1 to 67.153.243.25467.153.243.255254
24567.153.244.0/2467.153.244.1 to 67.153.244.25467.153.244.255254
24667.153.245.0/2467.153.245.1 to 67.153.245.25467.153.245.255254
24767.153.246.0/2467.153.246.1 to 67.153.246.25467.153.246.255254
24867.153.247.0/2467.153.247.1 to 67.153.247.25467.153.247.255254
24967.153.248.0/2467.153.248.1 to 67.153.248.25467.153.248.255254
25067.153.249.0/2467.153.249.1 to 67.153.249.25467.153.249.255254
25167.153.250.0/2467.153.250.1 to 67.153.250.25467.153.250.255254
25267.153.251.0/2467.153.251.1 to 67.153.251.25467.153.251.255254
25367.153.252.0/2467.153.252.1 to 67.153.252.25467.153.252.255254
25467.153.253.0/2467.153.253.1 to 67.153.253.25467.153.253.255254
25567.153.254.0/2467.153.254.1 to 67.153.254.25467.153.254.255254
25667.153.255.0/2467.153.255.1 to 67.153.255.25467.153.255.255254

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