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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.

Network79.72.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
79.72.0.0
Broadcast address
79.75.255.255
First usable
79.72.0.1
Last usable
79.75.255.254
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 4F480000 · Integer 1330118656 to 1330380799
Reverse DNS zones
72.79.in-addr.arpa
73.79.in-addr.arpa
74.79.in-addr.arpa
75.79.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
Address01001111.01001000.00000000.0000000079.72.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01001111.01001000.00000000.0000000079.72.0.0
Broadcast01001111.01001011.11111111.1111111179.75.255.255
Split into smaller subnets/23
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

79.72.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
179.72.0.0/2379.72.0.1 to 79.72.1.25479.72.1.255510
279.72.2.0/2379.72.2.1 to 79.72.3.25479.72.3.255510
379.72.4.0/2379.72.4.1 to 79.72.5.25479.72.5.255510
479.72.6.0/2379.72.6.1 to 79.72.7.25479.72.7.255510
579.72.8.0/2379.72.8.1 to 79.72.9.25479.72.9.255510
679.72.10.0/2379.72.10.1 to 79.72.11.25479.72.11.255510
779.72.12.0/2379.72.12.1 to 79.72.13.25479.72.13.255510
879.72.14.0/2379.72.14.1 to 79.72.15.25479.72.15.255510
979.72.16.0/2379.72.16.1 to 79.72.17.25479.72.17.255510
1079.72.18.0/2379.72.18.1 to 79.72.19.25479.72.19.255510
1179.72.20.0/2379.72.20.1 to 79.72.21.25479.72.21.255510
1279.72.22.0/2379.72.22.1 to 79.72.23.25479.72.23.255510
1379.72.24.0/2379.72.24.1 to 79.72.25.25479.72.25.255510
1479.72.26.0/2379.72.26.1 to 79.72.27.25479.72.27.255510
1579.72.28.0/2379.72.28.1 to 79.72.29.25479.72.29.255510
1679.72.30.0/2379.72.30.1 to 79.72.31.25479.72.31.255510
1779.72.32.0/2379.72.32.1 to 79.72.33.25479.72.33.255510
1879.72.34.0/2379.72.34.1 to 79.72.35.25479.72.35.255510
1979.72.36.0/2379.72.36.1 to 79.72.37.25479.72.37.255510
2079.72.38.0/2379.72.38.1 to 79.72.39.25479.72.39.255510
2179.72.40.0/2379.72.40.1 to 79.72.41.25479.72.41.255510
2279.72.42.0/2379.72.42.1 to 79.72.43.25479.72.43.255510
2379.72.44.0/2379.72.44.1 to 79.72.45.25479.72.45.255510
2479.72.46.0/2379.72.46.1 to 79.72.47.25479.72.47.255510
2579.72.48.0/2379.72.48.1 to 79.72.49.25479.72.49.255510
2679.72.50.0/2379.72.50.1 to 79.72.51.25479.72.51.255510
2779.72.52.0/2379.72.52.1 to 79.72.53.25479.72.53.255510
2879.72.54.0/2379.72.54.1 to 79.72.55.25479.72.55.255510
2979.72.56.0/2379.72.56.1 to 79.72.57.25479.72.57.255510
3079.72.58.0/2379.72.58.1 to 79.72.59.25479.72.59.255510
3179.72.60.0/2379.72.60.1 to 79.72.61.25479.72.61.255510
3279.72.62.0/2379.72.62.1 to 79.72.63.25479.72.63.255510
3379.72.64.0/2379.72.64.1 to 79.72.65.25479.72.65.255510
3479.72.66.0/2379.72.66.1 to 79.72.67.25479.72.67.255510
3579.72.68.0/2379.72.68.1 to 79.72.69.25479.72.69.255510
3679.72.70.0/2379.72.70.1 to 79.72.71.25479.72.71.255510
3779.72.72.0/2379.72.72.1 to 79.72.73.25479.72.73.255510
3879.72.74.0/2379.72.74.1 to 79.72.75.25479.72.75.255510
3979.72.76.0/2379.72.76.1 to 79.72.77.25479.72.77.255510
4079.72.78.0/2379.72.78.1 to 79.72.79.25479.72.79.255510
4179.72.80.0/2379.72.80.1 to 79.72.81.25479.72.81.255510
4279.72.82.0/2379.72.82.1 to 79.72.83.25479.72.83.255510
4379.72.84.0/2379.72.84.1 to 79.72.85.25479.72.85.255510
4479.72.86.0/2379.72.86.1 to 79.72.87.25479.72.87.255510
4579.72.88.0/2379.72.88.1 to 79.72.89.25479.72.89.255510
4679.72.90.0/2379.72.90.1 to 79.72.91.25479.72.91.255510
4779.72.92.0/2379.72.92.1 to 79.72.93.25479.72.93.255510
4879.72.94.0/2379.72.94.1 to 79.72.95.25479.72.95.255510
4979.72.96.0/2379.72.96.1 to 79.72.97.25479.72.97.255510
5079.72.98.0/2379.72.98.1 to 79.72.99.25479.72.99.255510
5179.72.100.0/2379.72.100.1 to 79.72.101.25479.72.101.255510
5279.72.102.0/2379.72.102.1 to 79.72.103.25479.72.103.255510
5379.72.104.0/2379.72.104.1 to 79.72.105.25479.72.105.255510
5479.72.106.0/2379.72.106.1 to 79.72.107.25479.72.107.255510
5579.72.108.0/2379.72.108.1 to 79.72.109.25479.72.109.255510
5679.72.110.0/2379.72.110.1 to 79.72.111.25479.72.111.255510
5779.72.112.0/2379.72.112.1 to 79.72.113.25479.72.113.255510
5879.72.114.0/2379.72.114.1 to 79.72.115.25479.72.115.255510
5979.72.116.0/2379.72.116.1 to 79.72.117.25479.72.117.255510
6079.72.118.0/2379.72.118.1 to 79.72.119.25479.72.119.255510
6179.72.120.0/2379.72.120.1 to 79.72.121.25479.72.121.255510
6279.72.122.0/2379.72.122.1 to 79.72.123.25479.72.123.255510
6379.72.124.0/2379.72.124.1 to 79.72.125.25479.72.125.255510
6479.72.126.0/2379.72.126.1 to 79.72.127.25479.72.127.255510
6579.72.128.0/2379.72.128.1 to 79.72.129.25479.72.129.255510
6679.72.130.0/2379.72.130.1 to 79.72.131.25479.72.131.255510
6779.72.132.0/2379.72.132.1 to 79.72.133.25479.72.133.255510
6879.72.134.0/2379.72.134.1 to 79.72.135.25479.72.135.255510
6979.72.136.0/2379.72.136.1 to 79.72.137.25479.72.137.255510
7079.72.138.0/2379.72.138.1 to 79.72.139.25479.72.139.255510
7179.72.140.0/2379.72.140.1 to 79.72.141.25479.72.141.255510
7279.72.142.0/2379.72.142.1 to 79.72.143.25479.72.143.255510
7379.72.144.0/2379.72.144.1 to 79.72.145.25479.72.145.255510
7479.72.146.0/2379.72.146.1 to 79.72.147.25479.72.147.255510
7579.72.148.0/2379.72.148.1 to 79.72.149.25479.72.149.255510
7679.72.150.0/2379.72.150.1 to 79.72.151.25479.72.151.255510
7779.72.152.0/2379.72.152.1 to 79.72.153.25479.72.153.255510
7879.72.154.0/2379.72.154.1 to 79.72.155.25479.72.155.255510
7979.72.156.0/2379.72.156.1 to 79.72.157.25479.72.157.255510
8079.72.158.0/2379.72.158.1 to 79.72.159.25479.72.159.255510
8179.72.160.0/2379.72.160.1 to 79.72.161.25479.72.161.255510
8279.72.162.0/2379.72.162.1 to 79.72.163.25479.72.163.255510
8379.72.164.0/2379.72.164.1 to 79.72.165.25479.72.165.255510
8479.72.166.0/2379.72.166.1 to 79.72.167.25479.72.167.255510
8579.72.168.0/2379.72.168.1 to 79.72.169.25479.72.169.255510
8679.72.170.0/2379.72.170.1 to 79.72.171.25479.72.171.255510
8779.72.172.0/2379.72.172.1 to 79.72.173.25479.72.173.255510
8879.72.174.0/2379.72.174.1 to 79.72.175.25479.72.175.255510
8979.72.176.0/2379.72.176.1 to 79.72.177.25479.72.177.255510
9079.72.178.0/2379.72.178.1 to 79.72.179.25479.72.179.255510
9179.72.180.0/2379.72.180.1 to 79.72.181.25479.72.181.255510
9279.72.182.0/2379.72.182.1 to 79.72.183.25479.72.183.255510
9379.72.184.0/2379.72.184.1 to 79.72.185.25479.72.185.255510
9479.72.186.0/2379.72.186.1 to 79.72.187.25479.72.187.255510
9579.72.188.0/2379.72.188.1 to 79.72.189.25479.72.189.255510
9679.72.190.0/2379.72.190.1 to 79.72.191.25479.72.191.255510
9779.72.192.0/2379.72.192.1 to 79.72.193.25479.72.193.255510
9879.72.194.0/2379.72.194.1 to 79.72.195.25479.72.195.255510
9979.72.196.0/2379.72.196.1 to 79.72.197.25479.72.197.255510
10079.72.198.0/2379.72.198.1 to 79.72.199.25479.72.199.255510
10179.72.200.0/2379.72.200.1 to 79.72.201.25479.72.201.255510
10279.72.202.0/2379.72.202.1 to 79.72.203.25479.72.203.255510
10379.72.204.0/2379.72.204.1 to 79.72.205.25479.72.205.255510
10479.72.206.0/2379.72.206.1 to 79.72.207.25479.72.207.255510
10579.72.208.0/2379.72.208.1 to 79.72.209.25479.72.209.255510
10679.72.210.0/2379.72.210.1 to 79.72.211.25479.72.211.255510
10779.72.212.0/2379.72.212.1 to 79.72.213.25479.72.213.255510
10879.72.214.0/2379.72.214.1 to 79.72.215.25479.72.215.255510
10979.72.216.0/2379.72.216.1 to 79.72.217.25479.72.217.255510
11079.72.218.0/2379.72.218.1 to 79.72.219.25479.72.219.255510
11179.72.220.0/2379.72.220.1 to 79.72.221.25479.72.221.255510
11279.72.222.0/2379.72.222.1 to 79.72.223.25479.72.223.255510
11379.72.224.0/2379.72.224.1 to 79.72.225.25479.72.225.255510
11479.72.226.0/2379.72.226.1 to 79.72.227.25479.72.227.255510
11579.72.228.0/2379.72.228.1 to 79.72.229.25479.72.229.255510
11679.72.230.0/2379.72.230.1 to 79.72.231.25479.72.231.255510
11779.72.232.0/2379.72.232.1 to 79.72.233.25479.72.233.255510
11879.72.234.0/2379.72.234.1 to 79.72.235.25479.72.235.255510
11979.72.236.0/2379.72.236.1 to 79.72.237.25479.72.237.255510
12079.72.238.0/2379.72.238.1 to 79.72.239.25479.72.239.255510
12179.72.240.0/2379.72.240.1 to 79.72.241.25479.72.241.255510
12279.72.242.0/2379.72.242.1 to 79.72.243.25479.72.243.255510
12379.72.244.0/2379.72.244.1 to 79.72.245.25479.72.245.255510
12479.72.246.0/2379.72.246.1 to 79.72.247.25479.72.247.255510
12579.72.248.0/2379.72.248.1 to 79.72.249.25479.72.249.255510
12679.72.250.0/2379.72.250.1 to 79.72.251.25479.72.251.255510
12779.72.252.0/2379.72.252.1 to 79.72.253.25479.72.253.255510
12879.72.254.0/2379.72.254.1 to 79.72.255.25479.72.255.255510
12979.73.0.0/2379.73.0.1 to 79.73.1.25479.73.1.255510
13079.73.2.0/2379.73.2.1 to 79.73.3.25479.73.3.255510
13179.73.4.0/2379.73.4.1 to 79.73.5.25479.73.5.255510
13279.73.6.0/2379.73.6.1 to 79.73.7.25479.73.7.255510
13379.73.8.0/2379.73.8.1 to 79.73.9.25479.73.9.255510
13479.73.10.0/2379.73.10.1 to 79.73.11.25479.73.11.255510
13579.73.12.0/2379.73.12.1 to 79.73.13.25479.73.13.255510
13679.73.14.0/2379.73.14.1 to 79.73.15.25479.73.15.255510
13779.73.16.0/2379.73.16.1 to 79.73.17.25479.73.17.255510
13879.73.18.0/2379.73.18.1 to 79.73.19.25479.73.19.255510
13979.73.20.0/2379.73.20.1 to 79.73.21.25479.73.21.255510
14079.73.22.0/2379.73.22.1 to 79.73.23.25479.73.23.255510
14179.73.24.0/2379.73.24.1 to 79.73.25.25479.73.25.255510
14279.73.26.0/2379.73.26.1 to 79.73.27.25479.73.27.255510
14379.73.28.0/2379.73.28.1 to 79.73.29.25479.73.29.255510
14479.73.30.0/2379.73.30.1 to 79.73.31.25479.73.31.255510
14579.73.32.0/2379.73.32.1 to 79.73.33.25479.73.33.255510
14679.73.34.0/2379.73.34.1 to 79.73.35.25479.73.35.255510
14779.73.36.0/2379.73.36.1 to 79.73.37.25479.73.37.255510
14879.73.38.0/2379.73.38.1 to 79.73.39.25479.73.39.255510
14979.73.40.0/2379.73.40.1 to 79.73.41.25479.73.41.255510
15079.73.42.0/2379.73.42.1 to 79.73.43.25479.73.43.255510
15179.73.44.0/2379.73.44.1 to 79.73.45.25479.73.45.255510
15279.73.46.0/2379.73.46.1 to 79.73.47.25479.73.47.255510
15379.73.48.0/2379.73.48.1 to 79.73.49.25479.73.49.255510
15479.73.50.0/2379.73.50.1 to 79.73.51.25479.73.51.255510
15579.73.52.0/2379.73.52.1 to 79.73.53.25479.73.53.255510
15679.73.54.0/2379.73.54.1 to 79.73.55.25479.73.55.255510
15779.73.56.0/2379.73.56.1 to 79.73.57.25479.73.57.255510
15879.73.58.0/2379.73.58.1 to 79.73.59.25479.73.59.255510
15979.73.60.0/2379.73.60.1 to 79.73.61.25479.73.61.255510
16079.73.62.0/2379.73.62.1 to 79.73.63.25479.73.63.255510
16179.73.64.0/2379.73.64.1 to 79.73.65.25479.73.65.255510
16279.73.66.0/2379.73.66.1 to 79.73.67.25479.73.67.255510
16379.73.68.0/2379.73.68.1 to 79.73.69.25479.73.69.255510
16479.73.70.0/2379.73.70.1 to 79.73.71.25479.73.71.255510
16579.73.72.0/2379.73.72.1 to 79.73.73.25479.73.73.255510
16679.73.74.0/2379.73.74.1 to 79.73.75.25479.73.75.255510
16779.73.76.0/2379.73.76.1 to 79.73.77.25479.73.77.255510
16879.73.78.0/2379.73.78.1 to 79.73.79.25479.73.79.255510
16979.73.80.0/2379.73.80.1 to 79.73.81.25479.73.81.255510
17079.73.82.0/2379.73.82.1 to 79.73.83.25479.73.83.255510
17179.73.84.0/2379.73.84.1 to 79.73.85.25479.73.85.255510
17279.73.86.0/2379.73.86.1 to 79.73.87.25479.73.87.255510
17379.73.88.0/2379.73.88.1 to 79.73.89.25479.73.89.255510
17479.73.90.0/2379.73.90.1 to 79.73.91.25479.73.91.255510
17579.73.92.0/2379.73.92.1 to 79.73.93.25479.73.93.255510
17679.73.94.0/2379.73.94.1 to 79.73.95.25479.73.95.255510
17779.73.96.0/2379.73.96.1 to 79.73.97.25479.73.97.255510
17879.73.98.0/2379.73.98.1 to 79.73.99.25479.73.99.255510
17979.73.100.0/2379.73.100.1 to 79.73.101.25479.73.101.255510
18079.73.102.0/2379.73.102.1 to 79.73.103.25479.73.103.255510
18179.73.104.0/2379.73.104.1 to 79.73.105.25479.73.105.255510
18279.73.106.0/2379.73.106.1 to 79.73.107.25479.73.107.255510
18379.73.108.0/2379.73.108.1 to 79.73.109.25479.73.109.255510
18479.73.110.0/2379.73.110.1 to 79.73.111.25479.73.111.255510
18579.73.112.0/2379.73.112.1 to 79.73.113.25479.73.113.255510
18679.73.114.0/2379.73.114.1 to 79.73.115.25479.73.115.255510
18779.73.116.0/2379.73.116.1 to 79.73.117.25479.73.117.255510
18879.73.118.0/2379.73.118.1 to 79.73.119.25479.73.119.255510
18979.73.120.0/2379.73.120.1 to 79.73.121.25479.73.121.255510
19079.73.122.0/2379.73.122.1 to 79.73.123.25479.73.123.255510
19179.73.124.0/2379.73.124.1 to 79.73.125.25479.73.125.255510
19279.73.126.0/2379.73.126.1 to 79.73.127.25479.73.127.255510
19379.73.128.0/2379.73.128.1 to 79.73.129.25479.73.129.255510
19479.73.130.0/2379.73.130.1 to 79.73.131.25479.73.131.255510
19579.73.132.0/2379.73.132.1 to 79.73.133.25479.73.133.255510
19679.73.134.0/2379.73.134.1 to 79.73.135.25479.73.135.255510
19779.73.136.0/2379.73.136.1 to 79.73.137.25479.73.137.255510
19879.73.138.0/2379.73.138.1 to 79.73.139.25479.73.139.255510
19979.73.140.0/2379.73.140.1 to 79.73.141.25479.73.141.255510
20079.73.142.0/2379.73.142.1 to 79.73.143.25479.73.143.255510
20179.73.144.0/2379.73.144.1 to 79.73.145.25479.73.145.255510
20279.73.146.0/2379.73.146.1 to 79.73.147.25479.73.147.255510
20379.73.148.0/2379.73.148.1 to 79.73.149.25479.73.149.255510
20479.73.150.0/2379.73.150.1 to 79.73.151.25479.73.151.255510
20579.73.152.0/2379.73.152.1 to 79.73.153.25479.73.153.255510
20679.73.154.0/2379.73.154.1 to 79.73.155.25479.73.155.255510
20779.73.156.0/2379.73.156.1 to 79.73.157.25479.73.157.255510
20879.73.158.0/2379.73.158.1 to 79.73.159.25479.73.159.255510
20979.73.160.0/2379.73.160.1 to 79.73.161.25479.73.161.255510
21079.73.162.0/2379.73.162.1 to 79.73.163.25479.73.163.255510
21179.73.164.0/2379.73.164.1 to 79.73.165.25479.73.165.255510
21279.73.166.0/2379.73.166.1 to 79.73.167.25479.73.167.255510
21379.73.168.0/2379.73.168.1 to 79.73.169.25479.73.169.255510
21479.73.170.0/2379.73.170.1 to 79.73.171.25479.73.171.255510
21579.73.172.0/2379.73.172.1 to 79.73.173.25479.73.173.255510
21679.73.174.0/2379.73.174.1 to 79.73.175.25479.73.175.255510
21779.73.176.0/2379.73.176.1 to 79.73.177.25479.73.177.255510
21879.73.178.0/2379.73.178.1 to 79.73.179.25479.73.179.255510
21979.73.180.0/2379.73.180.1 to 79.73.181.25479.73.181.255510
22079.73.182.0/2379.73.182.1 to 79.73.183.25479.73.183.255510
22179.73.184.0/2379.73.184.1 to 79.73.185.25479.73.185.255510
22279.73.186.0/2379.73.186.1 to 79.73.187.25479.73.187.255510
22379.73.188.0/2379.73.188.1 to 79.73.189.25479.73.189.255510
22479.73.190.0/2379.73.190.1 to 79.73.191.25479.73.191.255510
22579.73.192.0/2379.73.192.1 to 79.73.193.25479.73.193.255510
22679.73.194.0/2379.73.194.1 to 79.73.195.25479.73.195.255510
22779.73.196.0/2379.73.196.1 to 79.73.197.25479.73.197.255510
22879.73.198.0/2379.73.198.1 to 79.73.199.25479.73.199.255510
22979.73.200.0/2379.73.200.1 to 79.73.201.25479.73.201.255510
23079.73.202.0/2379.73.202.1 to 79.73.203.25479.73.203.255510
23179.73.204.0/2379.73.204.1 to 79.73.205.25479.73.205.255510
23279.73.206.0/2379.73.206.1 to 79.73.207.25479.73.207.255510
23379.73.208.0/2379.73.208.1 to 79.73.209.25479.73.209.255510
23479.73.210.0/2379.73.210.1 to 79.73.211.25479.73.211.255510
23579.73.212.0/2379.73.212.1 to 79.73.213.25479.73.213.255510
23679.73.214.0/2379.73.214.1 to 79.73.215.25479.73.215.255510
23779.73.216.0/2379.73.216.1 to 79.73.217.25479.73.217.255510
23879.73.218.0/2379.73.218.1 to 79.73.219.25479.73.219.255510
23979.73.220.0/2379.73.220.1 to 79.73.221.25479.73.221.255510
24079.73.222.0/2379.73.222.1 to 79.73.223.25479.73.223.255510
24179.73.224.0/2379.73.224.1 to 79.73.225.25479.73.225.255510
24279.73.226.0/2379.73.226.1 to 79.73.227.25479.73.227.255510
24379.73.228.0/2379.73.228.1 to 79.73.229.25479.73.229.255510
24479.73.230.0/2379.73.230.1 to 79.73.231.25479.73.231.255510
24579.73.232.0/2379.73.232.1 to 79.73.233.25479.73.233.255510
24679.73.234.0/2379.73.234.1 to 79.73.235.25479.73.235.255510
24779.73.236.0/2379.73.236.1 to 79.73.237.25479.73.237.255510
24879.73.238.0/2379.73.238.1 to 79.73.239.25479.73.239.255510
24979.73.240.0/2379.73.240.1 to 79.73.241.25479.73.241.255510
25079.73.242.0/2379.73.242.1 to 79.73.243.25479.73.243.255510
25179.73.244.0/2379.73.244.1 to 79.73.245.25479.73.245.255510
25279.73.246.0/2379.73.246.1 to 79.73.247.25479.73.247.255510
25379.73.248.0/2379.73.248.1 to 79.73.249.25479.73.249.255510
25479.73.250.0/2379.73.250.1 to 79.73.251.25479.73.251.255510
25579.73.252.0/2379.73.252.1 to 79.73.253.25479.73.253.255510
25679.73.254.0/2379.73.254.1 to 79.73.255.25479.73.255.255510

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

About this tool

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

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

Common questions

Why are two addresses lost in every IPv4 subnet?

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

What size of IPv6 network should a LAN use?

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

What is a wildcard mask?

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

Which ranges can I use inside an office?

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