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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.

Network79.232.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
79.232.0.0
Broadcast address
79.239.255.255
First usable
79.232.0.1
Last usable
79.239.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 4FE80000 · Integer 1340604416 to 1341128703
Reverse DNS zones
232.79.in-addr.arpa
233.79.in-addr.arpa
234.79.in-addr.arpa
235.79.in-addr.arpa
236.79.in-addr.arpa
237.79.in-addr.arpa
238.79.in-addr.arpa
239.79.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01001111.11101000.00000000.0000000079.232.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01001111.11101000.00000000.0000000079.232.0.0
Broadcast01001111.11101111.11111111.1111111179.239.255.255
Split into smaller subnets/21
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

79.232.0.0/13 makes 256 subnets of /21.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
179.232.0.0/2179.232.0.1 to 79.232.7.25479.232.7.2552,046
279.232.8.0/2179.232.8.1 to 79.232.15.25479.232.15.2552,046
379.232.16.0/2179.232.16.1 to 79.232.23.25479.232.23.2552,046
479.232.24.0/2179.232.24.1 to 79.232.31.25479.232.31.2552,046
579.232.32.0/2179.232.32.1 to 79.232.39.25479.232.39.2552,046
679.232.40.0/2179.232.40.1 to 79.232.47.25479.232.47.2552,046
779.232.48.0/2179.232.48.1 to 79.232.55.25479.232.55.2552,046
879.232.56.0/2179.232.56.1 to 79.232.63.25479.232.63.2552,046
979.232.64.0/2179.232.64.1 to 79.232.71.25479.232.71.2552,046
1079.232.72.0/2179.232.72.1 to 79.232.79.25479.232.79.2552,046
1179.232.80.0/2179.232.80.1 to 79.232.87.25479.232.87.2552,046
1279.232.88.0/2179.232.88.1 to 79.232.95.25479.232.95.2552,046
1379.232.96.0/2179.232.96.1 to 79.232.103.25479.232.103.2552,046
1479.232.104.0/2179.232.104.1 to 79.232.111.25479.232.111.2552,046
1579.232.112.0/2179.232.112.1 to 79.232.119.25479.232.119.2552,046
1679.232.120.0/2179.232.120.1 to 79.232.127.25479.232.127.2552,046
1779.232.128.0/2179.232.128.1 to 79.232.135.25479.232.135.2552,046
1879.232.136.0/2179.232.136.1 to 79.232.143.25479.232.143.2552,046
1979.232.144.0/2179.232.144.1 to 79.232.151.25479.232.151.2552,046
2079.232.152.0/2179.232.152.1 to 79.232.159.25479.232.159.2552,046
2179.232.160.0/2179.232.160.1 to 79.232.167.25479.232.167.2552,046
2279.232.168.0/2179.232.168.1 to 79.232.175.25479.232.175.2552,046
2379.232.176.0/2179.232.176.1 to 79.232.183.25479.232.183.2552,046
2479.232.184.0/2179.232.184.1 to 79.232.191.25479.232.191.2552,046
2579.232.192.0/2179.232.192.1 to 79.232.199.25479.232.199.2552,046
2679.232.200.0/2179.232.200.1 to 79.232.207.25479.232.207.2552,046
2779.232.208.0/2179.232.208.1 to 79.232.215.25479.232.215.2552,046
2879.232.216.0/2179.232.216.1 to 79.232.223.25479.232.223.2552,046
2979.232.224.0/2179.232.224.1 to 79.232.231.25479.232.231.2552,046
3079.232.232.0/2179.232.232.1 to 79.232.239.25479.232.239.2552,046
3179.232.240.0/2179.232.240.1 to 79.232.247.25479.232.247.2552,046
3279.232.248.0/2179.232.248.1 to 79.232.255.25479.232.255.2552,046
3379.233.0.0/2179.233.0.1 to 79.233.7.25479.233.7.2552,046
3479.233.8.0/2179.233.8.1 to 79.233.15.25479.233.15.2552,046
3579.233.16.0/2179.233.16.1 to 79.233.23.25479.233.23.2552,046
3679.233.24.0/2179.233.24.1 to 79.233.31.25479.233.31.2552,046
3779.233.32.0/2179.233.32.1 to 79.233.39.25479.233.39.2552,046
3879.233.40.0/2179.233.40.1 to 79.233.47.25479.233.47.2552,046
3979.233.48.0/2179.233.48.1 to 79.233.55.25479.233.55.2552,046
4079.233.56.0/2179.233.56.1 to 79.233.63.25479.233.63.2552,046
4179.233.64.0/2179.233.64.1 to 79.233.71.25479.233.71.2552,046
4279.233.72.0/2179.233.72.1 to 79.233.79.25479.233.79.2552,046
4379.233.80.0/2179.233.80.1 to 79.233.87.25479.233.87.2552,046
4479.233.88.0/2179.233.88.1 to 79.233.95.25479.233.95.2552,046
4579.233.96.0/2179.233.96.1 to 79.233.103.25479.233.103.2552,046
4679.233.104.0/2179.233.104.1 to 79.233.111.25479.233.111.2552,046
4779.233.112.0/2179.233.112.1 to 79.233.119.25479.233.119.2552,046
4879.233.120.0/2179.233.120.1 to 79.233.127.25479.233.127.2552,046
4979.233.128.0/2179.233.128.1 to 79.233.135.25479.233.135.2552,046
5079.233.136.0/2179.233.136.1 to 79.233.143.25479.233.143.2552,046
5179.233.144.0/2179.233.144.1 to 79.233.151.25479.233.151.2552,046
5279.233.152.0/2179.233.152.1 to 79.233.159.25479.233.159.2552,046
5379.233.160.0/2179.233.160.1 to 79.233.167.25479.233.167.2552,046
5479.233.168.0/2179.233.168.1 to 79.233.175.25479.233.175.2552,046
5579.233.176.0/2179.233.176.1 to 79.233.183.25479.233.183.2552,046
5679.233.184.0/2179.233.184.1 to 79.233.191.25479.233.191.2552,046
5779.233.192.0/2179.233.192.1 to 79.233.199.25479.233.199.2552,046
5879.233.200.0/2179.233.200.1 to 79.233.207.25479.233.207.2552,046
5979.233.208.0/2179.233.208.1 to 79.233.215.25479.233.215.2552,046
6079.233.216.0/2179.233.216.1 to 79.233.223.25479.233.223.2552,046
6179.233.224.0/2179.233.224.1 to 79.233.231.25479.233.231.2552,046
6279.233.232.0/2179.233.232.1 to 79.233.239.25479.233.239.2552,046
6379.233.240.0/2179.233.240.1 to 79.233.247.25479.233.247.2552,046
6479.233.248.0/2179.233.248.1 to 79.233.255.25479.233.255.2552,046
6579.234.0.0/2179.234.0.1 to 79.234.7.25479.234.7.2552,046
6679.234.8.0/2179.234.8.1 to 79.234.15.25479.234.15.2552,046
6779.234.16.0/2179.234.16.1 to 79.234.23.25479.234.23.2552,046
6879.234.24.0/2179.234.24.1 to 79.234.31.25479.234.31.2552,046
6979.234.32.0/2179.234.32.1 to 79.234.39.25479.234.39.2552,046
7079.234.40.0/2179.234.40.1 to 79.234.47.25479.234.47.2552,046
7179.234.48.0/2179.234.48.1 to 79.234.55.25479.234.55.2552,046
7279.234.56.0/2179.234.56.1 to 79.234.63.25479.234.63.2552,046
7379.234.64.0/2179.234.64.1 to 79.234.71.25479.234.71.2552,046
7479.234.72.0/2179.234.72.1 to 79.234.79.25479.234.79.2552,046
7579.234.80.0/2179.234.80.1 to 79.234.87.25479.234.87.2552,046
7679.234.88.0/2179.234.88.1 to 79.234.95.25479.234.95.2552,046
7779.234.96.0/2179.234.96.1 to 79.234.103.25479.234.103.2552,046
7879.234.104.0/2179.234.104.1 to 79.234.111.25479.234.111.2552,046
7979.234.112.0/2179.234.112.1 to 79.234.119.25479.234.119.2552,046
8079.234.120.0/2179.234.120.1 to 79.234.127.25479.234.127.2552,046
8179.234.128.0/2179.234.128.1 to 79.234.135.25479.234.135.2552,046
8279.234.136.0/2179.234.136.1 to 79.234.143.25479.234.143.2552,046
8379.234.144.0/2179.234.144.1 to 79.234.151.25479.234.151.2552,046
8479.234.152.0/2179.234.152.1 to 79.234.159.25479.234.159.2552,046
8579.234.160.0/2179.234.160.1 to 79.234.167.25479.234.167.2552,046
8679.234.168.0/2179.234.168.1 to 79.234.175.25479.234.175.2552,046
8779.234.176.0/2179.234.176.1 to 79.234.183.25479.234.183.2552,046
8879.234.184.0/2179.234.184.1 to 79.234.191.25479.234.191.2552,046
8979.234.192.0/2179.234.192.1 to 79.234.199.25479.234.199.2552,046
9079.234.200.0/2179.234.200.1 to 79.234.207.25479.234.207.2552,046
9179.234.208.0/2179.234.208.1 to 79.234.215.25479.234.215.2552,046
9279.234.216.0/2179.234.216.1 to 79.234.223.25479.234.223.2552,046
9379.234.224.0/2179.234.224.1 to 79.234.231.25479.234.231.2552,046
9479.234.232.0/2179.234.232.1 to 79.234.239.25479.234.239.2552,046
9579.234.240.0/2179.234.240.1 to 79.234.247.25479.234.247.2552,046
9679.234.248.0/2179.234.248.1 to 79.234.255.25479.234.255.2552,046
9779.235.0.0/2179.235.0.1 to 79.235.7.25479.235.7.2552,046
9879.235.8.0/2179.235.8.1 to 79.235.15.25479.235.15.2552,046
9979.235.16.0/2179.235.16.1 to 79.235.23.25479.235.23.2552,046
10079.235.24.0/2179.235.24.1 to 79.235.31.25479.235.31.2552,046
10179.235.32.0/2179.235.32.1 to 79.235.39.25479.235.39.2552,046
10279.235.40.0/2179.235.40.1 to 79.235.47.25479.235.47.2552,046
10379.235.48.0/2179.235.48.1 to 79.235.55.25479.235.55.2552,046
10479.235.56.0/2179.235.56.1 to 79.235.63.25479.235.63.2552,046
10579.235.64.0/2179.235.64.1 to 79.235.71.25479.235.71.2552,046
10679.235.72.0/2179.235.72.1 to 79.235.79.25479.235.79.2552,046
10779.235.80.0/2179.235.80.1 to 79.235.87.25479.235.87.2552,046
10879.235.88.0/2179.235.88.1 to 79.235.95.25479.235.95.2552,046
10979.235.96.0/2179.235.96.1 to 79.235.103.25479.235.103.2552,046
11079.235.104.0/2179.235.104.1 to 79.235.111.25479.235.111.2552,046
11179.235.112.0/2179.235.112.1 to 79.235.119.25479.235.119.2552,046
11279.235.120.0/2179.235.120.1 to 79.235.127.25479.235.127.2552,046
11379.235.128.0/2179.235.128.1 to 79.235.135.25479.235.135.2552,046
11479.235.136.0/2179.235.136.1 to 79.235.143.25479.235.143.2552,046
11579.235.144.0/2179.235.144.1 to 79.235.151.25479.235.151.2552,046
11679.235.152.0/2179.235.152.1 to 79.235.159.25479.235.159.2552,046
11779.235.160.0/2179.235.160.1 to 79.235.167.25479.235.167.2552,046
11879.235.168.0/2179.235.168.1 to 79.235.175.25479.235.175.2552,046
11979.235.176.0/2179.235.176.1 to 79.235.183.25479.235.183.2552,046
12079.235.184.0/2179.235.184.1 to 79.235.191.25479.235.191.2552,046
12179.235.192.0/2179.235.192.1 to 79.235.199.25479.235.199.2552,046
12279.235.200.0/2179.235.200.1 to 79.235.207.25479.235.207.2552,046
12379.235.208.0/2179.235.208.1 to 79.235.215.25479.235.215.2552,046
12479.235.216.0/2179.235.216.1 to 79.235.223.25479.235.223.2552,046
12579.235.224.0/2179.235.224.1 to 79.235.231.25479.235.231.2552,046
12679.235.232.0/2179.235.232.1 to 79.235.239.25479.235.239.2552,046
12779.235.240.0/2179.235.240.1 to 79.235.247.25479.235.247.2552,046
12879.235.248.0/2179.235.248.1 to 79.235.255.25479.235.255.2552,046
12979.236.0.0/2179.236.0.1 to 79.236.7.25479.236.7.2552,046
13079.236.8.0/2179.236.8.1 to 79.236.15.25479.236.15.2552,046
13179.236.16.0/2179.236.16.1 to 79.236.23.25479.236.23.2552,046
13279.236.24.0/2179.236.24.1 to 79.236.31.25479.236.31.2552,046
13379.236.32.0/2179.236.32.1 to 79.236.39.25479.236.39.2552,046
13479.236.40.0/2179.236.40.1 to 79.236.47.25479.236.47.2552,046
13579.236.48.0/2179.236.48.1 to 79.236.55.25479.236.55.2552,046
13679.236.56.0/2179.236.56.1 to 79.236.63.25479.236.63.2552,046
13779.236.64.0/2179.236.64.1 to 79.236.71.25479.236.71.2552,046
13879.236.72.0/2179.236.72.1 to 79.236.79.25479.236.79.2552,046
13979.236.80.0/2179.236.80.1 to 79.236.87.25479.236.87.2552,046
14079.236.88.0/2179.236.88.1 to 79.236.95.25479.236.95.2552,046
14179.236.96.0/2179.236.96.1 to 79.236.103.25479.236.103.2552,046
14279.236.104.0/2179.236.104.1 to 79.236.111.25479.236.111.2552,046
14379.236.112.0/2179.236.112.1 to 79.236.119.25479.236.119.2552,046
14479.236.120.0/2179.236.120.1 to 79.236.127.25479.236.127.2552,046
14579.236.128.0/2179.236.128.1 to 79.236.135.25479.236.135.2552,046
14679.236.136.0/2179.236.136.1 to 79.236.143.25479.236.143.2552,046
14779.236.144.0/2179.236.144.1 to 79.236.151.25479.236.151.2552,046
14879.236.152.0/2179.236.152.1 to 79.236.159.25479.236.159.2552,046
14979.236.160.0/2179.236.160.1 to 79.236.167.25479.236.167.2552,046
15079.236.168.0/2179.236.168.1 to 79.236.175.25479.236.175.2552,046
15179.236.176.0/2179.236.176.1 to 79.236.183.25479.236.183.2552,046
15279.236.184.0/2179.236.184.1 to 79.236.191.25479.236.191.2552,046
15379.236.192.0/2179.236.192.1 to 79.236.199.25479.236.199.2552,046
15479.236.200.0/2179.236.200.1 to 79.236.207.25479.236.207.2552,046
15579.236.208.0/2179.236.208.1 to 79.236.215.25479.236.215.2552,046
15679.236.216.0/2179.236.216.1 to 79.236.223.25479.236.223.2552,046
15779.236.224.0/2179.236.224.1 to 79.236.231.25479.236.231.2552,046
15879.236.232.0/2179.236.232.1 to 79.236.239.25479.236.239.2552,046
15979.236.240.0/2179.236.240.1 to 79.236.247.25479.236.247.2552,046
16079.236.248.0/2179.236.248.1 to 79.236.255.25479.236.255.2552,046
16179.237.0.0/2179.237.0.1 to 79.237.7.25479.237.7.2552,046
16279.237.8.0/2179.237.8.1 to 79.237.15.25479.237.15.2552,046
16379.237.16.0/2179.237.16.1 to 79.237.23.25479.237.23.2552,046
16479.237.24.0/2179.237.24.1 to 79.237.31.25479.237.31.2552,046
16579.237.32.0/2179.237.32.1 to 79.237.39.25479.237.39.2552,046
16679.237.40.0/2179.237.40.1 to 79.237.47.25479.237.47.2552,046
16779.237.48.0/2179.237.48.1 to 79.237.55.25479.237.55.2552,046
16879.237.56.0/2179.237.56.1 to 79.237.63.25479.237.63.2552,046
16979.237.64.0/2179.237.64.1 to 79.237.71.25479.237.71.2552,046
17079.237.72.0/2179.237.72.1 to 79.237.79.25479.237.79.2552,046
17179.237.80.0/2179.237.80.1 to 79.237.87.25479.237.87.2552,046
17279.237.88.0/2179.237.88.1 to 79.237.95.25479.237.95.2552,046
17379.237.96.0/2179.237.96.1 to 79.237.103.25479.237.103.2552,046
17479.237.104.0/2179.237.104.1 to 79.237.111.25479.237.111.2552,046
17579.237.112.0/2179.237.112.1 to 79.237.119.25479.237.119.2552,046
17679.237.120.0/2179.237.120.1 to 79.237.127.25479.237.127.2552,046
17779.237.128.0/2179.237.128.1 to 79.237.135.25479.237.135.2552,046
17879.237.136.0/2179.237.136.1 to 79.237.143.25479.237.143.2552,046
17979.237.144.0/2179.237.144.1 to 79.237.151.25479.237.151.2552,046
18079.237.152.0/2179.237.152.1 to 79.237.159.25479.237.159.2552,046
18179.237.160.0/2179.237.160.1 to 79.237.167.25479.237.167.2552,046
18279.237.168.0/2179.237.168.1 to 79.237.175.25479.237.175.2552,046
18379.237.176.0/2179.237.176.1 to 79.237.183.25479.237.183.2552,046
18479.237.184.0/2179.237.184.1 to 79.237.191.25479.237.191.2552,046
18579.237.192.0/2179.237.192.1 to 79.237.199.25479.237.199.2552,046
18679.237.200.0/2179.237.200.1 to 79.237.207.25479.237.207.2552,046
18779.237.208.0/2179.237.208.1 to 79.237.215.25479.237.215.2552,046
18879.237.216.0/2179.237.216.1 to 79.237.223.25479.237.223.2552,046
18979.237.224.0/2179.237.224.1 to 79.237.231.25479.237.231.2552,046
19079.237.232.0/2179.237.232.1 to 79.237.239.25479.237.239.2552,046
19179.237.240.0/2179.237.240.1 to 79.237.247.25479.237.247.2552,046
19279.237.248.0/2179.237.248.1 to 79.237.255.25479.237.255.2552,046
19379.238.0.0/2179.238.0.1 to 79.238.7.25479.238.7.2552,046
19479.238.8.0/2179.238.8.1 to 79.238.15.25479.238.15.2552,046
19579.238.16.0/2179.238.16.1 to 79.238.23.25479.238.23.2552,046
19679.238.24.0/2179.238.24.1 to 79.238.31.25479.238.31.2552,046
19779.238.32.0/2179.238.32.1 to 79.238.39.25479.238.39.2552,046
19879.238.40.0/2179.238.40.1 to 79.238.47.25479.238.47.2552,046
19979.238.48.0/2179.238.48.1 to 79.238.55.25479.238.55.2552,046
20079.238.56.0/2179.238.56.1 to 79.238.63.25479.238.63.2552,046
20179.238.64.0/2179.238.64.1 to 79.238.71.25479.238.71.2552,046
20279.238.72.0/2179.238.72.1 to 79.238.79.25479.238.79.2552,046
20379.238.80.0/2179.238.80.1 to 79.238.87.25479.238.87.2552,046
20479.238.88.0/2179.238.88.1 to 79.238.95.25479.238.95.2552,046
20579.238.96.0/2179.238.96.1 to 79.238.103.25479.238.103.2552,046
20679.238.104.0/2179.238.104.1 to 79.238.111.25479.238.111.2552,046
20779.238.112.0/2179.238.112.1 to 79.238.119.25479.238.119.2552,046
20879.238.120.0/2179.238.120.1 to 79.238.127.25479.238.127.2552,046
20979.238.128.0/2179.238.128.1 to 79.238.135.25479.238.135.2552,046
21079.238.136.0/2179.238.136.1 to 79.238.143.25479.238.143.2552,046
21179.238.144.0/2179.238.144.1 to 79.238.151.25479.238.151.2552,046
21279.238.152.0/2179.238.152.1 to 79.238.159.25479.238.159.2552,046
21379.238.160.0/2179.238.160.1 to 79.238.167.25479.238.167.2552,046
21479.238.168.0/2179.238.168.1 to 79.238.175.25479.238.175.2552,046
21579.238.176.0/2179.238.176.1 to 79.238.183.25479.238.183.2552,046
21679.238.184.0/2179.238.184.1 to 79.238.191.25479.238.191.2552,046
21779.238.192.0/2179.238.192.1 to 79.238.199.25479.238.199.2552,046
21879.238.200.0/2179.238.200.1 to 79.238.207.25479.238.207.2552,046
21979.238.208.0/2179.238.208.1 to 79.238.215.25479.238.215.2552,046
22079.238.216.0/2179.238.216.1 to 79.238.223.25479.238.223.2552,046
22179.238.224.0/2179.238.224.1 to 79.238.231.25479.238.231.2552,046
22279.238.232.0/2179.238.232.1 to 79.238.239.25479.238.239.2552,046
22379.238.240.0/2179.238.240.1 to 79.238.247.25479.238.247.2552,046
22479.238.248.0/2179.238.248.1 to 79.238.255.25479.238.255.2552,046
22579.239.0.0/2179.239.0.1 to 79.239.7.25479.239.7.2552,046
22679.239.8.0/2179.239.8.1 to 79.239.15.25479.239.15.2552,046
22779.239.16.0/2179.239.16.1 to 79.239.23.25479.239.23.2552,046
22879.239.24.0/2179.239.24.1 to 79.239.31.25479.239.31.2552,046
22979.239.32.0/2179.239.32.1 to 79.239.39.25479.239.39.2552,046
23079.239.40.0/2179.239.40.1 to 79.239.47.25479.239.47.2552,046
23179.239.48.0/2179.239.48.1 to 79.239.55.25479.239.55.2552,046
23279.239.56.0/2179.239.56.1 to 79.239.63.25479.239.63.2552,046
23379.239.64.0/2179.239.64.1 to 79.239.71.25479.239.71.2552,046
23479.239.72.0/2179.239.72.1 to 79.239.79.25479.239.79.2552,046
23579.239.80.0/2179.239.80.1 to 79.239.87.25479.239.87.2552,046
23679.239.88.0/2179.239.88.1 to 79.239.95.25479.239.95.2552,046
23779.239.96.0/2179.239.96.1 to 79.239.103.25479.239.103.2552,046
23879.239.104.0/2179.239.104.1 to 79.239.111.25479.239.111.2552,046
23979.239.112.0/2179.239.112.1 to 79.239.119.25479.239.119.2552,046
24079.239.120.0/2179.239.120.1 to 79.239.127.25479.239.127.2552,046
24179.239.128.0/2179.239.128.1 to 79.239.135.25479.239.135.2552,046
24279.239.136.0/2179.239.136.1 to 79.239.143.25479.239.143.2552,046
24379.239.144.0/2179.239.144.1 to 79.239.151.25479.239.151.2552,046
24479.239.152.0/2179.239.152.1 to 79.239.159.25479.239.159.2552,046
24579.239.160.0/2179.239.160.1 to 79.239.167.25479.239.167.2552,046
24679.239.168.0/2179.239.168.1 to 79.239.175.25479.239.175.2552,046
24779.239.176.0/2179.239.176.1 to 79.239.183.25479.239.183.2552,046
24879.239.184.0/2179.239.184.1 to 79.239.191.25479.239.191.2552,046
24979.239.192.0/2179.239.192.1 to 79.239.199.25479.239.199.2552,046
25079.239.200.0/2179.239.200.1 to 79.239.207.25479.239.207.2552,046
25179.239.208.0/2179.239.208.1 to 79.239.215.25479.239.215.2552,046
25279.239.216.0/2179.239.216.1 to 79.239.223.25479.239.223.2552,046
25379.239.224.0/2179.239.224.1 to 79.239.231.25479.239.231.2552,046
25479.239.232.0/2179.239.232.1 to 79.239.239.25479.239.239.2552,046
25579.239.240.0/2179.239.240.1 to 79.239.247.25479.239.247.2552,046
25679.239.248.0/2179.239.248.1 to 79.239.255.25479.239.255.2552,046

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.