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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.

Network35.167.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
35.167.0.0
Broadcast address
35.167.255.255
First usable
35.167.0.1
Last usable
35.167.255.254
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 23A70000 · Integer 598147072 to 598212607
Reverse DNS zone
167.35.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00100011.10100111..00000000.0000000035.167.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00100011.10100111..00000000.0000000035.167.0.0
Broadcast00100011.10100111..11111111.1111111135.167.255.255
Split into smaller subnets/24

35.167.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
135.167.0.0/2435.167.0.1 to 35.167.0.25435.167.0.255254
235.167.1.0/2435.167.1.1 to 35.167.1.25435.167.1.255254
335.167.2.0/2435.167.2.1 to 35.167.2.25435.167.2.255254
435.167.3.0/2435.167.3.1 to 35.167.3.25435.167.3.255254
535.167.4.0/2435.167.4.1 to 35.167.4.25435.167.4.255254
635.167.5.0/2435.167.5.1 to 35.167.5.25435.167.5.255254
735.167.6.0/2435.167.6.1 to 35.167.6.25435.167.6.255254
835.167.7.0/2435.167.7.1 to 35.167.7.25435.167.7.255254
935.167.8.0/2435.167.8.1 to 35.167.8.25435.167.8.255254
1035.167.9.0/2435.167.9.1 to 35.167.9.25435.167.9.255254
1135.167.10.0/2435.167.10.1 to 35.167.10.25435.167.10.255254
1235.167.11.0/2435.167.11.1 to 35.167.11.25435.167.11.255254
1335.167.12.0/2435.167.12.1 to 35.167.12.25435.167.12.255254
1435.167.13.0/2435.167.13.1 to 35.167.13.25435.167.13.255254
1535.167.14.0/2435.167.14.1 to 35.167.14.25435.167.14.255254
1635.167.15.0/2435.167.15.1 to 35.167.15.25435.167.15.255254
1735.167.16.0/2435.167.16.1 to 35.167.16.25435.167.16.255254
1835.167.17.0/2435.167.17.1 to 35.167.17.25435.167.17.255254
1935.167.18.0/2435.167.18.1 to 35.167.18.25435.167.18.255254
2035.167.19.0/2435.167.19.1 to 35.167.19.25435.167.19.255254
2135.167.20.0/2435.167.20.1 to 35.167.20.25435.167.20.255254
2235.167.21.0/2435.167.21.1 to 35.167.21.25435.167.21.255254
2335.167.22.0/2435.167.22.1 to 35.167.22.25435.167.22.255254
2435.167.23.0/2435.167.23.1 to 35.167.23.25435.167.23.255254
2535.167.24.0/2435.167.24.1 to 35.167.24.25435.167.24.255254
2635.167.25.0/2435.167.25.1 to 35.167.25.25435.167.25.255254
2735.167.26.0/2435.167.26.1 to 35.167.26.25435.167.26.255254
2835.167.27.0/2435.167.27.1 to 35.167.27.25435.167.27.255254
2935.167.28.0/2435.167.28.1 to 35.167.28.25435.167.28.255254
3035.167.29.0/2435.167.29.1 to 35.167.29.25435.167.29.255254
3135.167.30.0/2435.167.30.1 to 35.167.30.25435.167.30.255254
3235.167.31.0/2435.167.31.1 to 35.167.31.25435.167.31.255254
3335.167.32.0/2435.167.32.1 to 35.167.32.25435.167.32.255254
3435.167.33.0/2435.167.33.1 to 35.167.33.25435.167.33.255254
3535.167.34.0/2435.167.34.1 to 35.167.34.25435.167.34.255254
3635.167.35.0/2435.167.35.1 to 35.167.35.25435.167.35.255254
3735.167.36.0/2435.167.36.1 to 35.167.36.25435.167.36.255254
3835.167.37.0/2435.167.37.1 to 35.167.37.25435.167.37.255254
3935.167.38.0/2435.167.38.1 to 35.167.38.25435.167.38.255254
4035.167.39.0/2435.167.39.1 to 35.167.39.25435.167.39.255254
4135.167.40.0/2435.167.40.1 to 35.167.40.25435.167.40.255254
4235.167.41.0/2435.167.41.1 to 35.167.41.25435.167.41.255254
4335.167.42.0/2435.167.42.1 to 35.167.42.25435.167.42.255254
4435.167.43.0/2435.167.43.1 to 35.167.43.25435.167.43.255254
4535.167.44.0/2435.167.44.1 to 35.167.44.25435.167.44.255254
4635.167.45.0/2435.167.45.1 to 35.167.45.25435.167.45.255254
4735.167.46.0/2435.167.46.1 to 35.167.46.25435.167.46.255254
4835.167.47.0/2435.167.47.1 to 35.167.47.25435.167.47.255254
4935.167.48.0/2435.167.48.1 to 35.167.48.25435.167.48.255254
5035.167.49.0/2435.167.49.1 to 35.167.49.25435.167.49.255254
5135.167.50.0/2435.167.50.1 to 35.167.50.25435.167.50.255254
5235.167.51.0/2435.167.51.1 to 35.167.51.25435.167.51.255254
5335.167.52.0/2435.167.52.1 to 35.167.52.25435.167.52.255254
5435.167.53.0/2435.167.53.1 to 35.167.53.25435.167.53.255254
5535.167.54.0/2435.167.54.1 to 35.167.54.25435.167.54.255254
5635.167.55.0/2435.167.55.1 to 35.167.55.25435.167.55.255254
5735.167.56.0/2435.167.56.1 to 35.167.56.25435.167.56.255254
5835.167.57.0/2435.167.57.1 to 35.167.57.25435.167.57.255254
5935.167.58.0/2435.167.58.1 to 35.167.58.25435.167.58.255254
6035.167.59.0/2435.167.59.1 to 35.167.59.25435.167.59.255254
6135.167.60.0/2435.167.60.1 to 35.167.60.25435.167.60.255254
6235.167.61.0/2435.167.61.1 to 35.167.61.25435.167.61.255254
6335.167.62.0/2435.167.62.1 to 35.167.62.25435.167.62.255254
6435.167.63.0/2435.167.63.1 to 35.167.63.25435.167.63.255254
6535.167.64.0/2435.167.64.1 to 35.167.64.25435.167.64.255254
6635.167.65.0/2435.167.65.1 to 35.167.65.25435.167.65.255254
6735.167.66.0/2435.167.66.1 to 35.167.66.25435.167.66.255254
6835.167.67.0/2435.167.67.1 to 35.167.67.25435.167.67.255254
6935.167.68.0/2435.167.68.1 to 35.167.68.25435.167.68.255254
7035.167.69.0/2435.167.69.1 to 35.167.69.25435.167.69.255254
7135.167.70.0/2435.167.70.1 to 35.167.70.25435.167.70.255254
7235.167.71.0/2435.167.71.1 to 35.167.71.25435.167.71.255254
7335.167.72.0/2435.167.72.1 to 35.167.72.25435.167.72.255254
7435.167.73.0/2435.167.73.1 to 35.167.73.25435.167.73.255254
7535.167.74.0/2435.167.74.1 to 35.167.74.25435.167.74.255254
7635.167.75.0/2435.167.75.1 to 35.167.75.25435.167.75.255254
7735.167.76.0/2435.167.76.1 to 35.167.76.25435.167.76.255254
7835.167.77.0/2435.167.77.1 to 35.167.77.25435.167.77.255254
7935.167.78.0/2435.167.78.1 to 35.167.78.25435.167.78.255254
8035.167.79.0/2435.167.79.1 to 35.167.79.25435.167.79.255254
8135.167.80.0/2435.167.80.1 to 35.167.80.25435.167.80.255254
8235.167.81.0/2435.167.81.1 to 35.167.81.25435.167.81.255254
8335.167.82.0/2435.167.82.1 to 35.167.82.25435.167.82.255254
8435.167.83.0/2435.167.83.1 to 35.167.83.25435.167.83.255254
8535.167.84.0/2435.167.84.1 to 35.167.84.25435.167.84.255254
8635.167.85.0/2435.167.85.1 to 35.167.85.25435.167.85.255254
8735.167.86.0/2435.167.86.1 to 35.167.86.25435.167.86.255254
8835.167.87.0/2435.167.87.1 to 35.167.87.25435.167.87.255254
8935.167.88.0/2435.167.88.1 to 35.167.88.25435.167.88.255254
9035.167.89.0/2435.167.89.1 to 35.167.89.25435.167.89.255254
9135.167.90.0/2435.167.90.1 to 35.167.90.25435.167.90.255254
9235.167.91.0/2435.167.91.1 to 35.167.91.25435.167.91.255254
9335.167.92.0/2435.167.92.1 to 35.167.92.25435.167.92.255254
9435.167.93.0/2435.167.93.1 to 35.167.93.25435.167.93.255254
9535.167.94.0/2435.167.94.1 to 35.167.94.25435.167.94.255254
9635.167.95.0/2435.167.95.1 to 35.167.95.25435.167.95.255254
9735.167.96.0/2435.167.96.1 to 35.167.96.25435.167.96.255254
9835.167.97.0/2435.167.97.1 to 35.167.97.25435.167.97.255254
9935.167.98.0/2435.167.98.1 to 35.167.98.25435.167.98.255254
10035.167.99.0/2435.167.99.1 to 35.167.99.25435.167.99.255254
10135.167.100.0/2435.167.100.1 to 35.167.100.25435.167.100.255254
10235.167.101.0/2435.167.101.1 to 35.167.101.25435.167.101.255254
10335.167.102.0/2435.167.102.1 to 35.167.102.25435.167.102.255254
10435.167.103.0/2435.167.103.1 to 35.167.103.25435.167.103.255254
10535.167.104.0/2435.167.104.1 to 35.167.104.25435.167.104.255254
10635.167.105.0/2435.167.105.1 to 35.167.105.25435.167.105.255254
10735.167.106.0/2435.167.106.1 to 35.167.106.25435.167.106.255254
10835.167.107.0/2435.167.107.1 to 35.167.107.25435.167.107.255254
10935.167.108.0/2435.167.108.1 to 35.167.108.25435.167.108.255254
11035.167.109.0/2435.167.109.1 to 35.167.109.25435.167.109.255254
11135.167.110.0/2435.167.110.1 to 35.167.110.25435.167.110.255254
11235.167.111.0/2435.167.111.1 to 35.167.111.25435.167.111.255254
11335.167.112.0/2435.167.112.1 to 35.167.112.25435.167.112.255254
11435.167.113.0/2435.167.113.1 to 35.167.113.25435.167.113.255254
11535.167.114.0/2435.167.114.1 to 35.167.114.25435.167.114.255254
11635.167.115.0/2435.167.115.1 to 35.167.115.25435.167.115.255254
11735.167.116.0/2435.167.116.1 to 35.167.116.25435.167.116.255254
11835.167.117.0/2435.167.117.1 to 35.167.117.25435.167.117.255254
11935.167.118.0/2435.167.118.1 to 35.167.118.25435.167.118.255254
12035.167.119.0/2435.167.119.1 to 35.167.119.25435.167.119.255254
12135.167.120.0/2435.167.120.1 to 35.167.120.25435.167.120.255254
12235.167.121.0/2435.167.121.1 to 35.167.121.25435.167.121.255254
12335.167.122.0/2435.167.122.1 to 35.167.122.25435.167.122.255254
12435.167.123.0/2435.167.123.1 to 35.167.123.25435.167.123.255254
12535.167.124.0/2435.167.124.1 to 35.167.124.25435.167.124.255254
12635.167.125.0/2435.167.125.1 to 35.167.125.25435.167.125.255254
12735.167.126.0/2435.167.126.1 to 35.167.126.25435.167.126.255254
12835.167.127.0/2435.167.127.1 to 35.167.127.25435.167.127.255254
12935.167.128.0/2435.167.128.1 to 35.167.128.25435.167.128.255254
13035.167.129.0/2435.167.129.1 to 35.167.129.25435.167.129.255254
13135.167.130.0/2435.167.130.1 to 35.167.130.25435.167.130.255254
13235.167.131.0/2435.167.131.1 to 35.167.131.25435.167.131.255254
13335.167.132.0/2435.167.132.1 to 35.167.132.25435.167.132.255254
13435.167.133.0/2435.167.133.1 to 35.167.133.25435.167.133.255254
13535.167.134.0/2435.167.134.1 to 35.167.134.25435.167.134.255254
13635.167.135.0/2435.167.135.1 to 35.167.135.25435.167.135.255254
13735.167.136.0/2435.167.136.1 to 35.167.136.25435.167.136.255254
13835.167.137.0/2435.167.137.1 to 35.167.137.25435.167.137.255254
13935.167.138.0/2435.167.138.1 to 35.167.138.25435.167.138.255254
14035.167.139.0/2435.167.139.1 to 35.167.139.25435.167.139.255254
14135.167.140.0/2435.167.140.1 to 35.167.140.25435.167.140.255254
14235.167.141.0/2435.167.141.1 to 35.167.141.25435.167.141.255254
14335.167.142.0/2435.167.142.1 to 35.167.142.25435.167.142.255254
14435.167.143.0/2435.167.143.1 to 35.167.143.25435.167.143.255254
14535.167.144.0/2435.167.144.1 to 35.167.144.25435.167.144.255254
14635.167.145.0/2435.167.145.1 to 35.167.145.25435.167.145.255254
14735.167.146.0/2435.167.146.1 to 35.167.146.25435.167.146.255254
14835.167.147.0/2435.167.147.1 to 35.167.147.25435.167.147.255254
14935.167.148.0/2435.167.148.1 to 35.167.148.25435.167.148.255254
15035.167.149.0/2435.167.149.1 to 35.167.149.25435.167.149.255254
15135.167.150.0/2435.167.150.1 to 35.167.150.25435.167.150.255254
15235.167.151.0/2435.167.151.1 to 35.167.151.25435.167.151.255254
15335.167.152.0/2435.167.152.1 to 35.167.152.25435.167.152.255254
15435.167.153.0/2435.167.153.1 to 35.167.153.25435.167.153.255254
15535.167.154.0/2435.167.154.1 to 35.167.154.25435.167.154.255254
15635.167.155.0/2435.167.155.1 to 35.167.155.25435.167.155.255254
15735.167.156.0/2435.167.156.1 to 35.167.156.25435.167.156.255254
15835.167.157.0/2435.167.157.1 to 35.167.157.25435.167.157.255254
15935.167.158.0/2435.167.158.1 to 35.167.158.25435.167.158.255254
16035.167.159.0/2435.167.159.1 to 35.167.159.25435.167.159.255254
16135.167.160.0/2435.167.160.1 to 35.167.160.25435.167.160.255254
16235.167.161.0/2435.167.161.1 to 35.167.161.25435.167.161.255254
16335.167.162.0/2435.167.162.1 to 35.167.162.25435.167.162.255254
16435.167.163.0/2435.167.163.1 to 35.167.163.25435.167.163.255254
16535.167.164.0/2435.167.164.1 to 35.167.164.25435.167.164.255254
16635.167.165.0/2435.167.165.1 to 35.167.165.25435.167.165.255254
16735.167.166.0/2435.167.166.1 to 35.167.166.25435.167.166.255254
16835.167.167.0/2435.167.167.1 to 35.167.167.25435.167.167.255254
16935.167.168.0/2435.167.168.1 to 35.167.168.25435.167.168.255254
17035.167.169.0/2435.167.169.1 to 35.167.169.25435.167.169.255254
17135.167.170.0/2435.167.170.1 to 35.167.170.25435.167.170.255254
17235.167.171.0/2435.167.171.1 to 35.167.171.25435.167.171.255254
17335.167.172.0/2435.167.172.1 to 35.167.172.25435.167.172.255254
17435.167.173.0/2435.167.173.1 to 35.167.173.25435.167.173.255254
17535.167.174.0/2435.167.174.1 to 35.167.174.25435.167.174.255254
17635.167.175.0/2435.167.175.1 to 35.167.175.25435.167.175.255254
17735.167.176.0/2435.167.176.1 to 35.167.176.25435.167.176.255254
17835.167.177.0/2435.167.177.1 to 35.167.177.25435.167.177.255254
17935.167.178.0/2435.167.178.1 to 35.167.178.25435.167.178.255254
18035.167.179.0/2435.167.179.1 to 35.167.179.25435.167.179.255254
18135.167.180.0/2435.167.180.1 to 35.167.180.25435.167.180.255254
18235.167.181.0/2435.167.181.1 to 35.167.181.25435.167.181.255254
18335.167.182.0/2435.167.182.1 to 35.167.182.25435.167.182.255254
18435.167.183.0/2435.167.183.1 to 35.167.183.25435.167.183.255254
18535.167.184.0/2435.167.184.1 to 35.167.184.25435.167.184.255254
18635.167.185.0/2435.167.185.1 to 35.167.185.25435.167.185.255254
18735.167.186.0/2435.167.186.1 to 35.167.186.25435.167.186.255254
18835.167.187.0/2435.167.187.1 to 35.167.187.25435.167.187.255254
18935.167.188.0/2435.167.188.1 to 35.167.188.25435.167.188.255254
19035.167.189.0/2435.167.189.1 to 35.167.189.25435.167.189.255254
19135.167.190.0/2435.167.190.1 to 35.167.190.25435.167.190.255254
19235.167.191.0/2435.167.191.1 to 35.167.191.25435.167.191.255254
19335.167.192.0/2435.167.192.1 to 35.167.192.25435.167.192.255254
19435.167.193.0/2435.167.193.1 to 35.167.193.25435.167.193.255254
19535.167.194.0/2435.167.194.1 to 35.167.194.25435.167.194.255254
19635.167.195.0/2435.167.195.1 to 35.167.195.25435.167.195.255254
19735.167.196.0/2435.167.196.1 to 35.167.196.25435.167.196.255254
19835.167.197.0/2435.167.197.1 to 35.167.197.25435.167.197.255254
19935.167.198.0/2435.167.198.1 to 35.167.198.25435.167.198.255254
20035.167.199.0/2435.167.199.1 to 35.167.199.25435.167.199.255254
20135.167.200.0/2435.167.200.1 to 35.167.200.25435.167.200.255254
20235.167.201.0/2435.167.201.1 to 35.167.201.25435.167.201.255254
20335.167.202.0/2435.167.202.1 to 35.167.202.25435.167.202.255254
20435.167.203.0/2435.167.203.1 to 35.167.203.25435.167.203.255254
20535.167.204.0/2435.167.204.1 to 35.167.204.25435.167.204.255254
20635.167.205.0/2435.167.205.1 to 35.167.205.25435.167.205.255254
20735.167.206.0/2435.167.206.1 to 35.167.206.25435.167.206.255254
20835.167.207.0/2435.167.207.1 to 35.167.207.25435.167.207.255254
20935.167.208.0/2435.167.208.1 to 35.167.208.25435.167.208.255254
21035.167.209.0/2435.167.209.1 to 35.167.209.25435.167.209.255254
21135.167.210.0/2435.167.210.1 to 35.167.210.25435.167.210.255254
21235.167.211.0/2435.167.211.1 to 35.167.211.25435.167.211.255254
21335.167.212.0/2435.167.212.1 to 35.167.212.25435.167.212.255254
21435.167.213.0/2435.167.213.1 to 35.167.213.25435.167.213.255254
21535.167.214.0/2435.167.214.1 to 35.167.214.25435.167.214.255254
21635.167.215.0/2435.167.215.1 to 35.167.215.25435.167.215.255254
21735.167.216.0/2435.167.216.1 to 35.167.216.25435.167.216.255254
21835.167.217.0/2435.167.217.1 to 35.167.217.25435.167.217.255254
21935.167.218.0/2435.167.218.1 to 35.167.218.25435.167.218.255254
22035.167.219.0/2435.167.219.1 to 35.167.219.25435.167.219.255254
22135.167.220.0/2435.167.220.1 to 35.167.220.25435.167.220.255254
22235.167.221.0/2435.167.221.1 to 35.167.221.25435.167.221.255254
22335.167.222.0/2435.167.222.1 to 35.167.222.25435.167.222.255254
22435.167.223.0/2435.167.223.1 to 35.167.223.25435.167.223.255254
22535.167.224.0/2435.167.224.1 to 35.167.224.25435.167.224.255254
22635.167.225.0/2435.167.225.1 to 35.167.225.25435.167.225.255254
22735.167.226.0/2435.167.226.1 to 35.167.226.25435.167.226.255254
22835.167.227.0/2435.167.227.1 to 35.167.227.25435.167.227.255254
22935.167.228.0/2435.167.228.1 to 35.167.228.25435.167.228.255254
23035.167.229.0/2435.167.229.1 to 35.167.229.25435.167.229.255254
23135.167.230.0/2435.167.230.1 to 35.167.230.25435.167.230.255254
23235.167.231.0/2435.167.231.1 to 35.167.231.25435.167.231.255254
23335.167.232.0/2435.167.232.1 to 35.167.232.25435.167.232.255254
23435.167.233.0/2435.167.233.1 to 35.167.233.25435.167.233.255254
23535.167.234.0/2435.167.234.1 to 35.167.234.25435.167.234.255254
23635.167.235.0/2435.167.235.1 to 35.167.235.25435.167.235.255254
23735.167.236.0/2435.167.236.1 to 35.167.236.25435.167.236.255254
23835.167.237.0/2435.167.237.1 to 35.167.237.25435.167.237.255254
23935.167.238.0/2435.167.238.1 to 35.167.238.25435.167.238.255254
24035.167.239.0/2435.167.239.1 to 35.167.239.25435.167.239.255254
24135.167.240.0/2435.167.240.1 to 35.167.240.25435.167.240.255254
24235.167.241.0/2435.167.241.1 to 35.167.241.25435.167.241.255254
24335.167.242.0/2435.167.242.1 to 35.167.242.25435.167.242.255254
24435.167.243.0/2435.167.243.1 to 35.167.243.25435.167.243.255254
24535.167.244.0/2435.167.244.1 to 35.167.244.25435.167.244.255254
24635.167.245.0/2435.167.245.1 to 35.167.245.25435.167.245.255254
24735.167.246.0/2435.167.246.1 to 35.167.246.25435.167.246.255254
24835.167.247.0/2435.167.247.1 to 35.167.247.25435.167.247.255254
24935.167.248.0/2435.167.248.1 to 35.167.248.25435.167.248.255254
25035.167.249.0/2435.167.249.1 to 35.167.249.25435.167.249.255254
25135.167.250.0/2435.167.250.1 to 35.167.250.25435.167.250.255254
25235.167.251.0/2435.167.251.1 to 35.167.251.25435.167.251.255254
25335.167.252.0/2435.167.252.1 to 35.167.252.25435.167.252.255254
25435.167.253.0/2435.167.253.1 to 35.167.253.25435.167.253.255254
25535.167.254.0/2435.167.254.1 to 35.167.254.25435.167.254.255254
25635.167.255.0/2435.167.255.1 to 35.167.255.25435.167.255.255254

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